diff --git a/api/maven-api-model/pom.xml b/api/maven-api-model/pom.xml
index 87d80b4cb1fa..042569852474 100644
--- a/api/maven-api-model/pom.xml
+++ b/api/maven-api-model/pom.xml
@@ -41,27 +41,6 @@ under the License.
 
   <build>
     <plugins>
-      <plugin>
-        <groupId>org.codehaus.mojo</groupId>
-        <artifactId>build-helper-maven-plugin</artifactId>
-        <version>3.2.0</version>
-        <executions>
-          <execution>
-            <id>attach-mdo</id>
-            <goals>
-              <goal>attach-artifact</goal>
-            </goals>
-            <configuration>
-              <artifacts>
-                <artifact>
-                  <file>src/main/mdo/maven.mdo</file>
-                  <type>mdo</type>
-                </artifact>
-              </artifacts>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
       <plugin>
         <groupId>org.codehaus.modello</groupId>
         <artifactId>modello-maven-plugin</artifactId>
@@ -73,14 +52,16 @@ under the License.
             </goals>
             <configuration>
               <version>4.2.0</version>
+              <velocityBasedir>${project.basedir}/../../src/mdo</velocityBasedir>
               <models>
                 <model>src/main/mdo/maven.mdo</model>
               </models>
               <templates>
-                <template>src/main/mdo/model.vm</template>
+                <template>model.vm</template>
               </templates>
               <params>
                 <param>packageModelV4=org.apache.maven.api.model</param>
+                <param>isMavenModel=true</param>
               </params>
             </configuration>
           </execution>
diff --git a/api/maven-api-model/src/main/mdo/model.vm b/api/maven-api-model/src/main/mdo/model.vm
deleted file mode 100644
index 664064531c64..000000000000
--- a/api/maven-api-model/src/main/mdo/model.vm
+++ /dev/null
@@ -1,558 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageModelV4}" )
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#foreach ( $class in $model.allClasses )
-  #set ( $ancestors = $Helper.ancestors( $class ) )
-  #set ( $allFields = [] )
-  #set ( $inheritedFields = [] )
-  #foreach ( $cl in $ancestors )
-    #if ( $cl != $class )
-      #set ( $dummy = $inheritedFields.addAll( $cl.getFields($version) ) )
-    #end
-    #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-  #end
-  #set ( $className = "${class.name}" )
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-  #if ( $class.name != "InputLocation" && $class.name != "InputSource" )
-    #set ( $types = { } )
-    #set ( $imports = $class.getClass().forName("java.util.TreeSet").newInstance() )
-    #set ( $dummy = $imports.add( "java.io.Serializable" ) )
-    #set ( $dummy = $imports.add( "java.util.Collections" ) )
-    #set ( $dummy = $imports.add( "java.util.HashMap" ) )
-    #set ( $dummy = $imports.add( "java.util.Map" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Experimental" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Generated" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Immutable" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Nonnull" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.NotThreadSafe" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.ThreadSafe" ) )
-    #foreach ( $field in $allFields )
-      #if ( $field.type == "java.util.List" )
-        #set ( $dummy = $imports.add( "java.util.ArrayList" ) )
-        #set ( $dummy = $imports.add( "java.util.Collection" ) )
-        #set ( $dummy = $imports.add( "java.util.List" ) )
-        #set ( $dummy = $types.put( $field, "List<" + $field.to + ">" ) )
-      #elseif ( $field.type == "java.util.Properties" )
-        #set ( $dummy = $imports.add( "java.util.Map" ) )
-        #set ( $dummy = $types.put( $field, "Map<String, String>" ) )
-      #elseif ( $field.type == "DOM" )
-        #set ( $dummy = $imports.add( "org.apache.maven.api.xml.XmlNode" ) )
-        #set ( $dummy = $types.put( $field, "XmlNode" ) )
-      #else
-        #set ( $fieldType = ${types.getOrDefault($field.type,$field.type)} )
-        #set ( $idx = $fieldType.lastIndexOf('.') )
-        #if ( $idx > 0 )
-          #set ( $dummy = $imports.add( $fieldType ) )
-          #set ( $dummy = $types.put( $fieldType, $fieldType.substring( $idx + 1 ) ) )
-        #end
-      #end
-    #end
-    #set ( $eq = "" )
-    #set ( $hc = "" )
-    #foreach ( $field in $allFields )
-      #if ( $field.identifier )
-        #set ( $dummy = $imports.add( "java.util.Objects" ) )
-        #set ( $dummy = $identifiers.add( $field ) )
-        #if ( $eq == "" )
-          #set ( $eq = "Objects.equals( this.${field.name}, that.${field.name} )" )
-        #else
-          #set ( $eq = "$eq && Objects.equals( this.${field.name}, that.${field.name} )" )
-        #end
-        #if ( $hc == "" )
-          #set ( $hc = "${field.name}" )
-        #else
-          #set ( $hc = "$hc, this.${field.name}" )
-        #end
-      #end
-    #end
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-    #foreach ( $imp in $imports )
-import $imp;
-    #end
-
-/**
-    #foreach ( $line in ${class.description.trim().split("\n")} )
- * ${line.trim()}
-    #end
- */
-@Experimental
-@Generated @ThreadSafe @Immutable
-public class ${class.name}
-    #if ( $class.superClass )
-    extends ${class.superClass}
-    #end
-    #if ( $locationTracking )
-    implements Serializable, InputLocationTracker
-    #else
-    implements Serializable
-    #end
-{
-    #if ( $class == $root )
-    final String modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-    /**
-      #foreach ( $line in ${field.description.trim().split("\n")} )
-     * ${line.trim()}
-      #end
-     */
-    final ${type} $field.name;
-    #end
-    #if ( $locationTracking )
-      #if ( ! $class.superClass )
-    /** Location of the xml element for this object. */
-    final InputLocation location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-    /** Location of the xml element for the field ${field.name}. */
-    final InputLocation ${field.name}Location;
-      #end
-      #if ( ! $class.superClass )
-    /** Other locations */
-    final Map<Object, InputLocation> locations;
-      #end
-    #end
-
-    /**
-      * Constructor for this class, package protected.
-      * @see Builder#build()
-      */
-    ${class.name}(
-    #if ( $class == $root )
-        String modelEncoding,
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $sep = "#if(${locationTracking}||$field!=${allFields[${allFields.size()} - 1]}),#end" )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-        $type $field.name${sep}
-    #end
-    #if ( $locationTracking )
-        Map<Object, InputLocation> locations,
-      #set ( $sep = "#if(${allFields.size()}>0),#end" )
-        InputLocation location${sep}
-      #foreach ( $field in $allFields )
-        #set ( $sep = "#if(${locationTracking}&&$field!=${allFields[${allFields.size()} - 1]}),#end" )
-        InputLocation ${field.name}Location${sep}
-      #end
-    #end
-    )
-    {
-    #if ( $class.superClass )
-        super(
-      #foreach ( $field in $inheritedFields )
-        #set ( $sep = "#if(${locationTracking}||$field!=${inheritedFields[${inheritedFields.size()} - 1]}),#end" )
-            ${field.name}${sep}
-      #end
-      #if ( $locationTracking )
-            locations,
-        #set ( $sep = "#if(${inheritedFields.size()}>0),#end" )
-            location${sep}
-        #foreach ( $field in $inheritedFields )
-          #set ( $sep = "#if(${locationTracking}&&$field!=${inheritedFields[${inheritedFields.size()} - 1]}),#end" )
-            ${field.name}Location${sep}
-        #end
-      #end
-        );
-    #end
-    #if ( $class == $root )
-        this.modelEncoding = modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #if ( $field.type == "java.util.List" || $field.type == "java.util.Properties" || $field.type == "java.util.Map" )
-        this.${field.name} = ImmutableCollections.copy( ${field.name} );
-      #else
-        this.${field.name} = ${field.name};
-      #end
-    #end
-    #if ( $locationTracking )
-      #if ( ! $class.superClass )
-        this.locations = ImmutableCollections.copy( locations );
-        this.location = location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-        this.${field.name}Location = ${field.name}Location;
-      #end
-    #end
-    }
-
-    #if ( ! $eq.empty )
-    @Override
-    public boolean equals( Object o )
-    {
-        if ( this == o )
-        {
-            return true;
-        }
-        if ( o == null || !( o instanceof ${class.name} ) )
-        {
-            return false;
-        }
-        ${class.name} that = ( ${class.name} ) o;
-        return ${eq};
-    }
-
-    @Override
-    public int hashCode()
-    {
-        return Objects.hash( ${hc} );
-    }
-
-    #end
-    #if ( $class == $root )
-    public String getModelEncoding()
-    {
-        return modelEncoding;
-    }
-
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $cap = $Helper.capitalise( $field.name ) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type == "boolean" || $type == "Boolean" )
-        #set ( $pfx = "is" )
-      #else
-        #set ( $pfx = "get" )
-      #end
-    /**
-      #set ( $desc = ${field.description.trim()} )
-      #foreach ( $line in ${desc.split("\n")} )
-     * ${line.trim()}
-      #end
-     *
-     * @return a {@code ${type}}
-     */
-      #if ( $field.type == "java.util.List" || $field.type == "java.util.Properties" )
-    @Nonnull
-      #end
-    public ${type} ${pfx}${cap}()
-    {
-        return this.${field.name};
-    }
-
-    #end
-    #if ( $locationTracking )
-    /**
-     * Gets the location of the specified field in the input source.
-     */
-    public InputLocation getLocation( Object key )
-    {
-        if ( key instanceof String )
-        {
-            switch ( ( String ) key )
-            {
-      #if ( ! $class.superClass )
-                case "":
-                    return location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-                case "${field.name}":
-                    return ${field.name}Location;
-      #end
-            }
-        }
-      #if ( $class.superClass )
-        return super.getLocation( key );
-      #else
-        return locations != null ? locations.get( key ) : null;
-      #end
-    }
-
-    #end
-    /**
-     * Creates a new builder with this object as the basis.
-     *
-     * @return a {@code Builder}
-     */
-    @Nonnull
-    public Builder with()
-    {
-        return newBuilder( this );
-    }
-    #foreach ( $field in $allFields )
-      #set ( $cap = $Helper.capitalise( $field.name ) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-    /**
-     * Creates a new {@code ${class.name}} instance using the specified ${field.name}.
-     *
-     * @param ${field.name} the new {@code $type} to use
-     * @return a {@code ${class.name}} with the specified ${field.name}
-     */
-    @Nonnull
-    public ${class.name} with${cap}( $type $field.name )
-    {
-        return with().${field.name}( $field.name ).build();
-    }
-    #end
-
-    /**
-     * Creates a new {@code ${class.name}} instance.
-     * Equivalent to {@code newInstance( true )}.
-     * @see #newInstance(boolean)
-     *
-     * @return a new {@code ${class.name}}
-     */
-    @Nonnull
-    public static ${class.name} newInstance()
-    {
-        return newInstance( true );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} instance using default values or not.
-     * Equivalent to {@code newBuilder( withDefaults ).build()}.
-     *
-     * @param withDefaults the boolean indicating whether default values should be used
-     * @return a new {@code ${class.name}}
-     */
-    @Nonnull
-    public static ${class.name} newInstance( boolean withDefaults )
-    {
-        return newBuilder( withDefaults ).build();
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance.
-     * Equivalent to {@code newBuilder( true )}.
-     * @see #newBuilder(boolean)
-     *
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder()
-    {
-        return newBuilder( true );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance using default values or not.
-     *
-     * @param withDefaults the boolean indicating whether default values should be used
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder( boolean withDefaults )
-    {
-        return new Builder( withDefaults );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance using the specified object as a basis.
-     * Equivalent to {@code newBuilder( from, false )}.
-     *
-     * @param from the {@code ${class.name}} instance to use as a basis
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder( ${class.name} from )
-    {
-        return newBuilder( from, false );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance using the specified object as a basis.
-     *
-     * @param from the {@code ${class.name}} instance to use as a basis
-     * @param forceCopy the boolean indicating if a copy should be forced
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder( ${class.name} from, boolean forceCopy )
-    {
-        return new Builder( from, forceCopy );
-    }
-
-    /**
-     * Builder class used to create ${class.name} instances.
-     * @see #with()
-     * @see #newBuilder()
-     */
-    @NotThreadSafe
-    public static class Builder
-    #if ( $class.superClass )
-        extends ${class.superClass}.Builder
-    #end
-    {
-        ${class.name} base;
-    #if ( $class == $root )
-        String modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-      #if ( $type == 'boolean' )
-        Boolean ${field.name};
-      #elseif ( $type == 'int' )
-        Integer ${field.name};
-      #else
-        ${type} ${field.name};
-    #end
-    #end
-    #if ( ! $class.superClass && $locationTracking )
-        Map<Object, InputLocation> locations;
-    #end
-
-        Builder( boolean withDefaults )
-        {
-    #if ( $class.superClass )
-            super( withDefaults );
-    #end
-            if ( withDefaults )
-            {
-    #foreach ( $field in $class.getFields($version) )
-      #if ( $field.defaultValue )
-        #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-        #if ( $field.type == "String" )
-                this.${field.name} = "${field.defaultValue}";
-        #elseif ( $field.type != "java.util.List" && $field.type != "java.util.Properties" )
-                this.${field.name} = ${field.defaultValue};
-        #end
-      #end
-    #end
-            }
-        }
-
-        Builder( ${class.name} base, boolean forceCopy )
-        {
-    #if ( $class.superClass )
-            super( base, forceCopy );
-    #end
-            if ( forceCopy )
-            {
-    #foreach ( $field in $class.getFields($version) )
-                this.${field.name} = base.${field.name};
-    #end
-            }
-            else
-            {
-                this.base = base;
-            }
-        }
-
-    #if ( $class == $root )
-        @Nonnull
-        public Builder modelEncoding( String modelEncoding )
-        {
-            this.modelEncoding = modelEncoding;
-            return this;
-        }
-
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-        @Nonnull
-        public Builder ${field.name}( ${type} ${field.name} )
-        {
-            this.${field.name} = ${field.name};
-            return this;
-        }
-
-    #end
-
-    #if ( $locationTracking )
-        @Nonnull
-        public Builder location( Object key, InputLocation location )
-        {
-            if ( location != null )
-            {
-                if ( this.locations == null )
-                {
-                    this.locations = new HashMap<>();
-                }
-                this.locations.put( key, location );
-            }
-            return this;
-        }
-
-    #end
-        @Nonnull
-        public ${class.name} build()
-        {
-            if ( base != null
-    #foreach ( $field in $allFields )
-                    && ( ${field.name} == null || ${field.name} == base.${field.name} )
-    #end
-            )
-            {
-                return base;
-            }
-    #if ( $locationTracking )
-            Map<Object, InputLocation> locations = null;
-            InputLocation location = null;
-      #foreach ( $field in $allFields )
-            InputLocation ${field.name}Location = null;
-      #end
-            if ( this.locations != null )
-            {
-                locations = this.locations;
-                location = locations.remove( "" );
-      #foreach ( $field in $allFields )
-                ${field.name}Location = locations.remove( "${field.name}" );
-      #end
-            }
-    #end
-            return new ${class.name}(
-    #if ( $class == $root )
-                modelEncoding != null ? modelEncoding : ( base != null ? base.modelEncoding : "UTF-8" ),
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $sep = "#if(${locationTracking}||$field!=${allFields[${allFields.size()} - 1]}),#end" )
-      #if ( $field.type == "boolean" || $field.type == "int" )
-                ${field.name} != null ? ${field.name} : ( base != null ? base.${field.name} : ${field.defaultValue} )${sep}
-      #else
-                ${field.name} != null ? ${field.name} : ( base != null ? base.${field.name} : null )${sep}
-      #end
-    #end
-    #if ( $locationTracking )
-                locations != null ? locations : ( base != null ? base.locations : null ),
-      #set ( $sep = "#if(${allFields.size()}>0),#end" )
-                location != null ? location : ( base != null ? base.location : null )${sep}
-      #foreach ( $field in $allFields )
-        #set ( $sep = "#if(${locationTracking}&&$field!=${allFields[${allFields.size()} - 1]}),#end" )
-                ${field.name}Location != null ? ${field.name}Location : ( base != null ? base.${field.name}Location : null )${sep}
-      #end
-    #end
-            );
-        }
-    }
-
-    #foreach ( $cs in $class.getCodeSegments($version) )
-$cs.code
-    #end
-}
-  #end
-#end
diff --git a/api/maven-api-settings/pom.xml b/api/maven-api-settings/pom.xml
index ae75044a5dd1..279225a474de 100644
--- a/api/maven-api-settings/pom.xml
+++ b/api/maven-api-settings/pom.xml
@@ -41,27 +41,6 @@ under the License.
 
   <build>
     <plugins>
-      <plugin>
-        <groupId>org.codehaus.mojo</groupId>
-        <artifactId>build-helper-maven-plugin</artifactId>
-        <version>3.2.0</version>
-        <executions>
-          <execution>
-            <id>attach-mdo</id>
-            <goals>
-              <goal>attach-artifact</goal>
-            </goals>
-            <configuration>
-              <artifacts>
-                <artifact>
-                  <file>src/main/mdo/settings.mdo</file>
-                  <type>mdo</type>
-                </artifact>
-              </artifacts>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
       <plugin>
         <groupId>org.codehaus.modello</groupId>
         <artifactId>modello-maven-plugin</artifactId>
@@ -73,11 +52,12 @@ under the License.
             </goals>
             <configuration>
               <version>2.0.0</version>
+              <velocityBasedir>${project.basedir}/../../src/mdo</velocityBasedir>
               <models>
                 <model>src/main/mdo/settings.mdo</model>
               </models>
               <templates>
-                <template>src/main/mdo/model.vm</template>
+                <template>model.vm</template>
               </templates>
               <params>
                 <param>packageModelV4=org.apache.maven.api.settings</param>
diff --git a/api/maven-api-settings/src/main/mdo/common.vm b/api/maven-api-settings/src/main/mdo/common.vm
deleted file mode 100644
index aa3d17a0398e..000000000000
--- a/api/maven-api-settings/src/main/mdo/common.vm
+++ /dev/null
@@ -1,21 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-##
-## Nothing special to do here
-##
\ No newline at end of file
diff --git a/api/maven-api-settings/src/main/mdo/model.vm b/api/maven-api-settings/src/main/mdo/model.vm
deleted file mode 100644
index 664064531c64..000000000000
--- a/api/maven-api-settings/src/main/mdo/model.vm
+++ /dev/null
@@ -1,558 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageModelV4}" )
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#foreach ( $class in $model.allClasses )
-  #set ( $ancestors = $Helper.ancestors( $class ) )
-  #set ( $allFields = [] )
-  #set ( $inheritedFields = [] )
-  #foreach ( $cl in $ancestors )
-    #if ( $cl != $class )
-      #set ( $dummy = $inheritedFields.addAll( $cl.getFields($version) ) )
-    #end
-    #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-  #end
-  #set ( $className = "${class.name}" )
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-  #if ( $class.name != "InputLocation" && $class.name != "InputSource" )
-    #set ( $types = { } )
-    #set ( $imports = $class.getClass().forName("java.util.TreeSet").newInstance() )
-    #set ( $dummy = $imports.add( "java.io.Serializable" ) )
-    #set ( $dummy = $imports.add( "java.util.Collections" ) )
-    #set ( $dummy = $imports.add( "java.util.HashMap" ) )
-    #set ( $dummy = $imports.add( "java.util.Map" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Experimental" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Generated" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Immutable" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Nonnull" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.NotThreadSafe" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.ThreadSafe" ) )
-    #foreach ( $field in $allFields )
-      #if ( $field.type == "java.util.List" )
-        #set ( $dummy = $imports.add( "java.util.ArrayList" ) )
-        #set ( $dummy = $imports.add( "java.util.Collection" ) )
-        #set ( $dummy = $imports.add( "java.util.List" ) )
-        #set ( $dummy = $types.put( $field, "List<" + $field.to + ">" ) )
-      #elseif ( $field.type == "java.util.Properties" )
-        #set ( $dummy = $imports.add( "java.util.Map" ) )
-        #set ( $dummy = $types.put( $field, "Map<String, String>" ) )
-      #elseif ( $field.type == "DOM" )
-        #set ( $dummy = $imports.add( "org.apache.maven.api.xml.XmlNode" ) )
-        #set ( $dummy = $types.put( $field, "XmlNode" ) )
-      #else
-        #set ( $fieldType = ${types.getOrDefault($field.type,$field.type)} )
-        #set ( $idx = $fieldType.lastIndexOf('.') )
-        #if ( $idx > 0 )
-          #set ( $dummy = $imports.add( $fieldType ) )
-          #set ( $dummy = $types.put( $fieldType, $fieldType.substring( $idx + 1 ) ) )
-        #end
-      #end
-    #end
-    #set ( $eq = "" )
-    #set ( $hc = "" )
-    #foreach ( $field in $allFields )
-      #if ( $field.identifier )
-        #set ( $dummy = $imports.add( "java.util.Objects" ) )
-        #set ( $dummy = $identifiers.add( $field ) )
-        #if ( $eq == "" )
-          #set ( $eq = "Objects.equals( this.${field.name}, that.${field.name} )" )
-        #else
-          #set ( $eq = "$eq && Objects.equals( this.${field.name}, that.${field.name} )" )
-        #end
-        #if ( $hc == "" )
-          #set ( $hc = "${field.name}" )
-        #else
-          #set ( $hc = "$hc, this.${field.name}" )
-        #end
-      #end
-    #end
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-    #foreach ( $imp in $imports )
-import $imp;
-    #end
-
-/**
-    #foreach ( $line in ${class.description.trim().split("\n")} )
- * ${line.trim()}
-    #end
- */
-@Experimental
-@Generated @ThreadSafe @Immutable
-public class ${class.name}
-    #if ( $class.superClass )
-    extends ${class.superClass}
-    #end
-    #if ( $locationTracking )
-    implements Serializable, InputLocationTracker
-    #else
-    implements Serializable
-    #end
-{
-    #if ( $class == $root )
-    final String modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-    /**
-      #foreach ( $line in ${field.description.trim().split("\n")} )
-     * ${line.trim()}
-      #end
-     */
-    final ${type} $field.name;
-    #end
-    #if ( $locationTracking )
-      #if ( ! $class.superClass )
-    /** Location of the xml element for this object. */
-    final InputLocation location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-    /** Location of the xml element for the field ${field.name}. */
-    final InputLocation ${field.name}Location;
-      #end
-      #if ( ! $class.superClass )
-    /** Other locations */
-    final Map<Object, InputLocation> locations;
-      #end
-    #end
-
-    /**
-      * Constructor for this class, package protected.
-      * @see Builder#build()
-      */
-    ${class.name}(
-    #if ( $class == $root )
-        String modelEncoding,
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $sep = "#if(${locationTracking}||$field!=${allFields[${allFields.size()} - 1]}),#end" )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-        $type $field.name${sep}
-    #end
-    #if ( $locationTracking )
-        Map<Object, InputLocation> locations,
-      #set ( $sep = "#if(${allFields.size()}>0),#end" )
-        InputLocation location${sep}
-      #foreach ( $field in $allFields )
-        #set ( $sep = "#if(${locationTracking}&&$field!=${allFields[${allFields.size()} - 1]}),#end" )
-        InputLocation ${field.name}Location${sep}
-      #end
-    #end
-    )
-    {
-    #if ( $class.superClass )
-        super(
-      #foreach ( $field in $inheritedFields )
-        #set ( $sep = "#if(${locationTracking}||$field!=${inheritedFields[${inheritedFields.size()} - 1]}),#end" )
-            ${field.name}${sep}
-      #end
-      #if ( $locationTracking )
-            locations,
-        #set ( $sep = "#if(${inheritedFields.size()}>0),#end" )
-            location${sep}
-        #foreach ( $field in $inheritedFields )
-          #set ( $sep = "#if(${locationTracking}&&$field!=${inheritedFields[${inheritedFields.size()} - 1]}),#end" )
-            ${field.name}Location${sep}
-        #end
-      #end
-        );
-    #end
-    #if ( $class == $root )
-        this.modelEncoding = modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #if ( $field.type == "java.util.List" || $field.type == "java.util.Properties" || $field.type == "java.util.Map" )
-        this.${field.name} = ImmutableCollections.copy( ${field.name} );
-      #else
-        this.${field.name} = ${field.name};
-      #end
-    #end
-    #if ( $locationTracking )
-      #if ( ! $class.superClass )
-        this.locations = ImmutableCollections.copy( locations );
-        this.location = location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-        this.${field.name}Location = ${field.name}Location;
-      #end
-    #end
-    }
-
-    #if ( ! $eq.empty )
-    @Override
-    public boolean equals( Object o )
-    {
-        if ( this == o )
-        {
-            return true;
-        }
-        if ( o == null || !( o instanceof ${class.name} ) )
-        {
-            return false;
-        }
-        ${class.name} that = ( ${class.name} ) o;
-        return ${eq};
-    }
-
-    @Override
-    public int hashCode()
-    {
-        return Objects.hash( ${hc} );
-    }
-
-    #end
-    #if ( $class == $root )
-    public String getModelEncoding()
-    {
-        return modelEncoding;
-    }
-
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $cap = $Helper.capitalise( $field.name ) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type == "boolean" || $type == "Boolean" )
-        #set ( $pfx = "is" )
-      #else
-        #set ( $pfx = "get" )
-      #end
-    /**
-      #set ( $desc = ${field.description.trim()} )
-      #foreach ( $line in ${desc.split("\n")} )
-     * ${line.trim()}
-      #end
-     *
-     * @return a {@code ${type}}
-     */
-      #if ( $field.type == "java.util.List" || $field.type == "java.util.Properties" )
-    @Nonnull
-      #end
-    public ${type} ${pfx}${cap}()
-    {
-        return this.${field.name};
-    }
-
-    #end
-    #if ( $locationTracking )
-    /**
-     * Gets the location of the specified field in the input source.
-     */
-    public InputLocation getLocation( Object key )
-    {
-        if ( key instanceof String )
-        {
-            switch ( ( String ) key )
-            {
-      #if ( ! $class.superClass )
-                case "":
-                    return location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-                case "${field.name}":
-                    return ${field.name}Location;
-      #end
-            }
-        }
-      #if ( $class.superClass )
-        return super.getLocation( key );
-      #else
-        return locations != null ? locations.get( key ) : null;
-      #end
-    }
-
-    #end
-    /**
-     * Creates a new builder with this object as the basis.
-     *
-     * @return a {@code Builder}
-     */
-    @Nonnull
-    public Builder with()
-    {
-        return newBuilder( this );
-    }
-    #foreach ( $field in $allFields )
-      #set ( $cap = $Helper.capitalise( $field.name ) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-    /**
-     * Creates a new {@code ${class.name}} instance using the specified ${field.name}.
-     *
-     * @param ${field.name} the new {@code $type} to use
-     * @return a {@code ${class.name}} with the specified ${field.name}
-     */
-    @Nonnull
-    public ${class.name} with${cap}( $type $field.name )
-    {
-        return with().${field.name}( $field.name ).build();
-    }
-    #end
-
-    /**
-     * Creates a new {@code ${class.name}} instance.
-     * Equivalent to {@code newInstance( true )}.
-     * @see #newInstance(boolean)
-     *
-     * @return a new {@code ${class.name}}
-     */
-    @Nonnull
-    public static ${class.name} newInstance()
-    {
-        return newInstance( true );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} instance using default values or not.
-     * Equivalent to {@code newBuilder( withDefaults ).build()}.
-     *
-     * @param withDefaults the boolean indicating whether default values should be used
-     * @return a new {@code ${class.name}}
-     */
-    @Nonnull
-    public static ${class.name} newInstance( boolean withDefaults )
-    {
-        return newBuilder( withDefaults ).build();
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance.
-     * Equivalent to {@code newBuilder( true )}.
-     * @see #newBuilder(boolean)
-     *
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder()
-    {
-        return newBuilder( true );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance using default values or not.
-     *
-     * @param withDefaults the boolean indicating whether default values should be used
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder( boolean withDefaults )
-    {
-        return new Builder( withDefaults );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance using the specified object as a basis.
-     * Equivalent to {@code newBuilder( from, false )}.
-     *
-     * @param from the {@code ${class.name}} instance to use as a basis
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder( ${class.name} from )
-    {
-        return newBuilder( from, false );
-    }
-
-    /**
-     * Creates a new {@code ${class.name}} builder instance using the specified object as a basis.
-     *
-     * @param from the {@code ${class.name}} instance to use as a basis
-     * @param forceCopy the boolean indicating if a copy should be forced
-     * @return a new {@code Builder}
-     */
-    @Nonnull
-    public static Builder newBuilder( ${class.name} from, boolean forceCopy )
-    {
-        return new Builder( from, forceCopy );
-    }
-
-    /**
-     * Builder class used to create ${class.name} instances.
-     * @see #with()
-     * @see #newBuilder()
-     */
-    @NotThreadSafe
-    public static class Builder
-    #if ( $class.superClass )
-        extends ${class.superClass}.Builder
-    #end
-    {
-        ${class.name} base;
-    #if ( $class == $root )
-        String modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-      #if ( $type == 'boolean' )
-        Boolean ${field.name};
-      #elseif ( $type == 'int' )
-        Integer ${field.name};
-      #else
-        ${type} ${field.name};
-    #end
-    #end
-    #if ( ! $class.superClass && $locationTracking )
-        Map<Object, InputLocation> locations;
-    #end
-
-        Builder( boolean withDefaults )
-        {
-    #if ( $class.superClass )
-            super( withDefaults );
-    #end
-            if ( withDefaults )
-            {
-    #foreach ( $field in $class.getFields($version) )
-      #if ( $field.defaultValue )
-        #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-        #if ( $field.type == "String" )
-                this.${field.name} = "${field.defaultValue}";
-        #elseif ( $field.type != "java.util.List" && $field.type != "java.util.Properties" )
-                this.${field.name} = ${field.defaultValue};
-        #end
-      #end
-    #end
-            }
-        }
-
-        Builder( ${class.name} base, boolean forceCopy )
-        {
-    #if ( $class.superClass )
-            super( base, forceCopy );
-    #end
-            if ( forceCopy )
-            {
-    #foreach ( $field in $class.getFields($version) )
-                this.${field.name} = base.${field.name};
-    #end
-            }
-            else
-            {
-                this.base = base;
-            }
-        }
-
-    #if ( $class == $root )
-        @Nonnull
-        public Builder modelEncoding( String modelEncoding )
-        {
-            this.modelEncoding = modelEncoding;
-            return this;
-        }
-
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-        @Nonnull
-        public Builder ${field.name}( ${type} ${field.name} )
-        {
-            this.${field.name} = ${field.name};
-            return this;
-        }
-
-    #end
-
-    #if ( $locationTracking )
-        @Nonnull
-        public Builder location( Object key, InputLocation location )
-        {
-            if ( location != null )
-            {
-                if ( this.locations == null )
-                {
-                    this.locations = new HashMap<>();
-                }
-                this.locations.put( key, location );
-            }
-            return this;
-        }
-
-    #end
-        @Nonnull
-        public ${class.name} build()
-        {
-            if ( base != null
-    #foreach ( $field in $allFields )
-                    && ( ${field.name} == null || ${field.name} == base.${field.name} )
-    #end
-            )
-            {
-                return base;
-            }
-    #if ( $locationTracking )
-            Map<Object, InputLocation> locations = null;
-            InputLocation location = null;
-      #foreach ( $field in $allFields )
-            InputLocation ${field.name}Location = null;
-      #end
-            if ( this.locations != null )
-            {
-                locations = this.locations;
-                location = locations.remove( "" );
-      #foreach ( $field in $allFields )
-                ${field.name}Location = locations.remove( "${field.name}" );
-      #end
-            }
-    #end
-            return new ${class.name}(
-    #if ( $class == $root )
-                modelEncoding != null ? modelEncoding : ( base != null ? base.modelEncoding : "UTF-8" ),
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $sep = "#if(${locationTracking}||$field!=${allFields[${allFields.size()} - 1]}),#end" )
-      #if ( $field.type == "boolean" || $field.type == "int" )
-                ${field.name} != null ? ${field.name} : ( base != null ? base.${field.name} : ${field.defaultValue} )${sep}
-      #else
-                ${field.name} != null ? ${field.name} : ( base != null ? base.${field.name} : null )${sep}
-      #end
-    #end
-    #if ( $locationTracking )
-                locations != null ? locations : ( base != null ? base.locations : null ),
-      #set ( $sep = "#if(${allFields.size()}>0),#end" )
-                location != null ? location : ( base != null ? base.location : null )${sep}
-      #foreach ( $field in $allFields )
-        #set ( $sep = "#if(${locationTracking}&&$field!=${allFields[${allFields.size()} - 1]}),#end" )
-                ${field.name}Location != null ? ${field.name}Location : ( base != null ? base.${field.name}Location : null )${sep}
-      #end
-    #end
-            );
-        }
-    }
-
-    #foreach ( $cs in $class.getCodeSegments($version) )
-$cs.code
-    #end
-}
-  #end
-#end
diff --git a/api/maven-api-toolchain/pom.xml b/api/maven-api-toolchain/pom.xml
index ea734f5dc1ca..f3e74c32e648 100644
--- a/api/maven-api-toolchain/pom.xml
+++ b/api/maven-api-toolchain/pom.xml
@@ -40,27 +40,6 @@ under the License.
 
   <build>
     <plugins>
-      <plugin>
-        <groupId>org.codehaus.mojo</groupId>
-        <artifactId>build-helper-maven-plugin</artifactId>
-        <version>3.2.0</version>
-        <executions>
-          <execution>
-            <id>attach-mdo</id>
-            <goals>
-              <goal>attach-artifact</goal>
-            </goals>
-            <configuration>
-              <artifacts>
-                <artifact>
-                  <file>src/main/mdo/toolchains.mdo</file>
-                  <type>mdo</type>
-                </artifact>
-              </artifacts>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
       <plugin>
         <groupId>org.codehaus.modello</groupId>
         <artifactId>modello-maven-plugin</artifactId>
@@ -72,11 +51,12 @@ under the License.
             </goals>
             <configuration>
               <version>1.1.0</version>
+              <velocityBasedir>${project.basedir}/../../src/mdo</velocityBasedir>
               <models>
                 <model>src/main/mdo/toolchains.mdo</model>
               </models>
               <templates>
-                <template>src/main/mdo/model.vm</template>
+                <template>model.vm</template>
               </templates>
               <params>
                 <param>packageModelV4=org.apache.maven.api.toolchain</param>
diff --git a/api/maven-api-toolchain/src/main/mdo/common.vm b/api/maven-api-toolchain/src/main/mdo/common.vm
deleted file mode 100644
index aa3d17a0398e..000000000000
--- a/api/maven-api-toolchain/src/main/mdo/common.vm
+++ /dev/null
@@ -1,21 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-##
-## Nothing special to do here
-##
\ No newline at end of file
diff --git a/maven-model/pom.xml b/maven-model/pom.xml
index 8fbd8317be57..56f03db5f109 100644
--- a/maven-model/pom.xml
+++ b/maven-model/pom.xml
@@ -46,43 +46,21 @@ under the License.
 
   <build>
     <plugins>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-dependency-plugin</artifactId>
-        <executions>
-          <execution>
-            <id>copy-maven.mdo</id>
-            <goals>
-              <goal>copy</goal>
-            </goals>
-            <phase>generate-sources</phase>
-            <configuration>
-              <artifactItems>
-                <artifactItem>
-                  <groupId>org.apache.maven</groupId>
-                  <artifactId>maven-api-model</artifactId>
-                  <version>${project.version}</version>
-                  <type>mdo</type>
-                  <outputDirectory>target/mdo/</outputDirectory>
-                  <destFileName>maven.mdo</destFileName>
-                </artifactItem>
-              </artifactItems>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
       <plugin>
         <groupId>org.codehaus.modello</groupId>
         <artifactId>modello-maven-plugin</artifactId>
         <configuration>
+          <basedir>${project.basedir}/../api/maven-api-model</basedir>
+          <velocityBasedir>${project.basedir}/../src/mdo</velocityBasedir>
           <version>4.0.0</version>
           <models>
-            <model>target/mdo/maven.mdo</model>
+            <model>src/main/mdo/maven.mdo</model>
           </models>
           <params>
             <param>packageModelV3=org.apache.maven.model</param>
             <param>packageModelV4=org.apache.maven.api.model</param>
             <param>packageToolV4=org.apache.maven.model.v4</param>
+            <param>isMavenModel=true</param>
           </params>
         </configuration>
         <executions>
@@ -103,7 +81,7 @@ under the License.
             <configuration>
               <version>4.1.0</version>
               <templates>
-                <template>src/main/mdo/model-v3.vm</template>
+                <template>model-v3-modified.vm</template>
               </templates>
             </configuration>
           </execution>
@@ -116,12 +94,12 @@ under the License.
             <configuration>
               <version>4.2.0</version>
               <templates>
-                <template>src/main/mdo/merger.vm</template>
-                <template>src/main/mdo/transformer.vm</template>
-                <template>src/main/mdo/reader.vm</template>
-                <template>src/main/mdo/reader-ex.vm</template>
-                <template>src/main/mdo/writer.vm</template>
-                <template>src/main/mdo/writer-ex.vm</template>
+                <template>merger.vm</template>
+                <template>transformer.vm</template>
+                <template>reader-modified.vm</template>
+                <template>reader-ex.vm</template>
+                <template>writer.vm</template>
+                <template>writer-ex.vm</template>
               </templates>
             </configuration>
           </execution>
diff --git a/maven-model/src/main/mdo/common.vm b/maven-model/src/main/mdo/common.vm
deleted file mode 100644
index 3c3f29cf7a27..000000000000
--- a/maven-model/src/main/mdo/common.vm
+++ /dev/null
@@ -1,31 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#
-##
-## The following loop code is required in order to change the type of the
-## pomFile attribute to a java.nio.file.Path.  Modello does not support this
-## type and loading a model with such a type would fail the modello validation.
-##
-#foreach ( $field in $model.getClass("Model", $version).allFields )
-  #if ( $field.name == "pomFile" )
-    #set ( $dummy = $field.setType("java.nio.file.Path") )
-  #end
-#end
-#set ( $locationTracking = true )
-#
\ No newline at end of file
diff --git a/maven-model/src/main/mdo/merger.vm b/maven-model/src/main/mdo/merger.vm
deleted file mode 100644
index 2cf9da482e94..000000000000
--- a/maven-model/src/main/mdo/merger.vm
+++ /dev/null
@@ -1,380 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Merger" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.ObjectStreamException;
-import java.util.AbstractList;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Properties;
-import java.util.Objects;
-import java.util.function.BinaryOperator;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.api.xml.XmlNode;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.Name};
-#end
-
-@Generated
-public class ${className}
-{
-
-    /**
-     * Merges the specified source object into the given target object.
-     *
-     * @param target The target object whose existing contents should be merged with the source, must not be
-     *            <code>null</code>.
-     * @param source The (read-only) source object that should be merged into the target object, may be
-     *            <code>null</code>.
-     * @param sourceDominant A flag indicating whether either the target object or the source object provides the
-     *            dominant data.
-     * @param hints A set of key-value pairs that customized merger implementations can use to carry domain-specific
-     *            information along, may be <code>null</code>.
-     */
-    public ${root.name} merge( ${root.name} target, ${root.name} source, boolean sourceDominant, Map<?, ?> hints )
-    {
-        Objects.requireNonNull( target, "target cannot be null" );
-        if ( source == null )
-        {
-            return target;
-        }
-        Map<Object, Object> context = new HashMap<>();
-        if ( hints != null )
-        {
-            context.putAll( hints );
-        }
-        return merge${root.name}( target, source, sourceDominant, context );
-    }
-
-#foreach ( $class in $model.allClasses )
-  #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-    #set ( $ancestors = $Helper.ancestors( $class ) )
-    #set ( $allFields = [] )
-    #foreach ( $cl in $ancestors )
-      #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-    #end
-    protected ${class.name} merge${class.name}( ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-        ${class.name}.Builder builder = ${class.name}.newBuilder( target );
-        merge${class.name}( builder, target, source, sourceDominant, context );
-        return builder.build();
-    }
-
-    protected void merge${class.name}( ${class.name}.Builder builder, ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-    #if ( $class.superClass )
-        merge${class.superClass}( builder, target ,source, sourceDominant, context );
-    #end
-    #foreach ( $field in $class.getFields($version) )
-        merge${field.modelClass.name}_${Helper.capitalise($field.name)}( builder, target, source, sourceDominant, context );
-    #end
-    }
-
-    #foreach ( $field in $allFields )
-      #set ( $capField = ${Helper.capitalise($field.name)} )
-    protected void merge${class.name}_${capField}( ${class.name}.Builder builder, ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-      #if ( $field.type == "String" )
-        String src = source.get${capField}();
-        String tgt = target.get${capField}();
-        if ( src != null && ( sourceDominant || tgt == null ) )
-        {
-            builder.${field.name}( src );
-        #if ( $locationTracking )
-            builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-        }
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-        builder.${field.name}( merge( target.get${capField}(), source.get${capField}(), sourceDominant, e -> e ) );
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-        Map<String, String> src = source.get${capField}();
-        if ( !src.isEmpty() )
-        {
-            Map<String, String> tgt = target.get${capField}();
-            if ( tgt.isEmpty() )
-            {
-                builder.${field.name}( src );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-            }
-            else
-            {
-                Map<String, String> merged = new HashMap<>();
-                merged.putAll( sourceDominant ? target.get${capField}() : source.get${capField}() );
-                merged.putAll( sourceDominant ? source.get${capField}() : target.get${capField}() );
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", InputLocation.merge( target.getLocation( "${field.name}" ), source.getLocation( "${field.name}" ), sourceDominant ) );
-        #end
-            }
-        }
-      #elseif ( $field.to && $field.multiplicity == "1" )
-        ${field.to} src = source.get${capField}();
-        if ( src != null )
-        {
-            ${field.to} tgt = target.get${capField}();
-            if ( tgt == null )
-            {
-                tgt = ${field.to}.newInstance( false );
-            }
-            ${field.to} merged = merge${field.to}( tgt, src, sourceDominant, context );
-            if ( merged == src )
-            {
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-            }
-            else if ( merged != tgt )
-            {
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", InputLocation.merge( target.getLocation( "${field.name}" ), source.getLocation( "${field.name}" ), sourceDominant ) );
-        #end
-            }
-        }
-      #elseif ( $field.to && $field.multiplicity == "*" )
-        builder.${field.name}( merge( target.get${capField}(), source.get${capField}(), sourceDominant, get${field.to}Key() ) );
-      #elseif ( $field.type == "DOM" )
-        XmlNode src = source.getConfiguration();
-        if ( src != null )
-        {
-            XmlNode tgt = target.getConfiguration();
-            if ( tgt == null )
-            {
-                builder.configuration( src );
-            }
-            else if ( sourceDominant )
-            {
-                builder.configuration( src.merge( tgt ) );
-            }
-            else
-            {
-                builder.configuration( tgt.merge( src ) );
-            }
-        }
-      #elseif ( $field.type == "boolean" )
-        if ( sourceDominant )
-        {
-            builder.${field.name}( source.is${capField}() );
-        }
-      #elseif ( $field.type == "int" || $field.type == "java.nio.file.Path" )
-        if ( sourceDominant )
-        {
-            builder.${field.name}( source.get${capField}() );
-        }
-      #else
-        // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    }
-    #end
-
-  #end
-#end
-
-#foreach ( $class in $model.allClasses )
-  #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-    protected KeyComputer<${class.name}> get${class.name}Key()
-    {
-        return v -> v;
-    }
-  #end
-#end
-
-    /**
-     * Use to compute keys for data structures
-     * @param <T> the data structure type
-     */
-    @FunctionalInterface
-    public interface KeyComputer<T> extends Function<T, Object>
-    {
-    }
-
-    /**
-     * Merge two lists
-     */
-    public static <T> List<T> merge( List<T> tgt, List<T> src, boolean sourceDominant, KeyComputer<T> computer )
-    {
-        return merge( tgt, src, computer, ( t, s ) -> sourceDominant ? s : t );
-    }
-
-    public static <T> List<T> merge( List<T> tgt, List<T> src, KeyComputer<T> computer, BinaryOperator<T> remapping )
-    {
-        if ( src.isEmpty() )
-        {
-            return tgt;
-        }
-
-        MergingList<T> list;
-        if ( tgt instanceof MergingList )
-        {
-            list = (MergingList<T>) tgt;
-        }
-        else
-        {
-            list = new MergingList<>( computer, src.size() + tgt.size() );
-            list.mergeAll( tgt, ( t, s ) -> s );
-        }
-
-        list.mergeAll( src, remapping );
-        return list;
-    }
-
-    /**
-     * Merging list
-     * @param <V>
-     */
-    private static class MergingList<V> extends AbstractList<V> implements java.io.Serializable
-    {
-
-        private final KeyComputer<V> keyComputer;
-        private Map<Object, V> map;
-        private List<V> list;
-
-        MergingList( KeyComputer<V> keyComputer, int initialCapacity )
-        {
-            this.map = new LinkedHashMap<>( initialCapacity );
-            this.keyComputer = keyComputer;
-        }
-
-        Object writeReplace() throws ObjectStreamException
-        {
-            return new ArrayList<>( this );
-        }
-
-        @Override
-        public Iterator<V> iterator()
-        {
-            if ( map != null )
-            {
-                return map.values().iterator();
-            }
-            else
-            {
-                return list.iterator();
-            }
-        }
-
-        void mergeAll( Collection<V> vs, BinaryOperator<V> remapping )
-        {
-            if ( map == null )
-            {
-                map = list.stream().collect( Collectors.toMap( keyComputer,
-                                                               Function.identity(),
-                                                               null,
-                                                               LinkedHashMap::new ) );
-
-                list = null;
-            }
-
-            if ( vs instanceof MergingList && ( (MergingList<V>) vs ).map != null )
-            {
-                for ( Map.Entry<Object, V> e : ( (MergingList<V>) vs ).map.entrySet() )
-                {
-                    Object key = e.getKey();
-                    V v = e.getValue();
-                    map.merge( key, v, remapping );
-                }
-            }
-            else
-            {
-                for ( V v : vs )
-                {
-                    Object key = keyComputer.apply( v );
-
-                    map.merge( key, v, remapping );
-                }
-            }
-        }
-
-        @Override
-        public boolean contains( Object o )
-        {
-            if ( map != null )
-            {
-                return map.containsValue( o );
-            }
-            else
-            {
-                return list.contains( o );
-            }
-        }
-
-        private List<V> asList()
-        {
-            if ( list == null )
-            {
-                list = new ArrayList<>( map.values() );
-                map = null;
-            }
-            return list;
-        }
-
-        @Override
-        public void add( int index, V element )
-        {
-            asList().add( index, element );
-        }
-
-        @Override
-        public V remove( int index )
-        {
-            return asList().remove( index );
-        }
-
-        @Override
-        public V get( int index )
-        {
-            return asList().get( index );
-        }
-
-        @Override
-        public int size()
-        {
-            if ( map != null )
-            {
-                return map.size();
-            }
-            else
-            {
-                return list.size();
-            }
-        }
-    }
-}
diff --git a/maven-model/src/main/mdo/writer.vm b/maven-model/src/main/mdo/writer.vm
deleted file mode 100644
index 7b2c805d3607..000000000000
--- a/maven-model/src/main/mdo/writer.vm
+++ /dev/null
@@ -1,331 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Xpp3Writer" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#set ( $rootXml = $Helper.xmlClassMetadata( $root ) )
-#set ( $rootTag = $rootXml.tagName )
-#set ( $rootUcapName = $Helper.capitalise( $root.name ) )
-#set ( $rootLcapName = $Helper.uncapitalise( $root.name ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.io.Reader;
-import java.io.Writer;
-import java.text.DateFormat;
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Properties;
-import java.util.Set;
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.api.xml.XmlNode;
-import org.apache.maven.internal.xml.XmlNodeBuilder;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.name};
-#end
-import org.codehaus.plexus.util.ReaderFactory;
-import org.codehaus.plexus.util.xml.pull.EntityReplacementMap;
-import org.codehaus.plexus.util.xml.pull.MXParser;
-import org.codehaus.plexus.util.xml.pull.MXSerializer;
-import org.codehaus.plexus.util.xml.pull.XmlPullParser;
-import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
-import org.codehaus.plexus.util.xml.pull.XmlSerializer;
-
-@Generated
-public class ${className}
-{
-      //--------------------------/
-     //- Class/Member Variables -/
-    //--------------------------/
-
-    /**
-     * Field NAMESPACE.
-     */
-    private static final String NAMESPACE = null;
-
-    /**
-     * Field fileComment.
-     */
-    private String fileComment = null;
-
-
-      //-----------/
-     //- Methods -/
-    //-----------/
-
-    /**
-     * Method setFileComment.
-     *
-     * @param fileComment a fileComment object.
-     */
-    public void setFileComment( String fileComment )
-    {
-        this.fileComment = fileComment;
-    } //-- void setFileComment( String )
-
-    /**
-     * Method write.
-     *
-     * @param writer a writer object
-     * @param ${rootLcapName} a ${root.name} object
-     * @throws java.io.IOException java.io.IOException if any
-     */
-    public void write( Writer writer, ${root.name} ${rootLcapName} )
-        throws java.io.IOException
-    {
-        XmlSerializer serializer = new MXSerializer();
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-indentation", "  " );
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-line-separator", "\n" );
-        serializer.setOutput( writer );
-        serializer.startDocument( ${rootLcapName}.getModelEncoding(), null );
-        write${root.name}( "$rootTag", ${rootLcapName}, serializer );
-        serializer.endDocument();
-    } //-- void write( Writer, ${root.name} )
-
-    /**
-     * Method write.
-     *
-     * @param stream a stream object
-     * @param ${rootLcapName} a ${root.name} object
-     * @throws java.io.IOException java.io.IOException if any
-     */
-    public void write( OutputStream stream, ${root.name} ${rootLcapName} )
-        throws java.io.IOException
-    {
-        XmlSerializer serializer = new MXSerializer();
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-indentation", "  " );
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-line-separator", "\n" );
-        serializer.setOutput( stream, ${rootLcapName}.getModelEncoding() );
-        serializer.startDocument( ${rootLcapName}.getModelEncoding(), null );
-        write${root.name}( "$rootTag", ${rootLcapName}, serializer );
-        serializer.endDocument();
-    } //-- void write( OutputStream, ${root.name} )
-
-    /**
-     * Method writeDomToSerializer.
-     *
-     * @param dom a dom object.
-     * @param serializer a serializer object.
-     * @throws java.io.IOException java.io.IOException if any.
-     */
-    protected void writeDomToSerializer( org.apache.maven.api.xml.XmlNode dom, XmlSerializer serializer )
-        throws java.io.IOException
-    {
-        serializer.startTag( NAMESPACE, dom.getName() );
-
-        for ( Map.Entry<String, String> attribute : dom.getAttributes().entrySet() )
-        {
-            serializer.attribute( NAMESPACE, attribute.getKey(), attribute.getValue() );
-        }
-        for ( XmlNode aChild : dom.getChildren() )
-        {
-            writeDomToSerializer( aChild, serializer );
-        }
-
-        String value = dom.getValue();
-        if ( value != null )
-        {
-            serializer.text( value );
-        }
-
-        serializer.endTag( NAMESPACE, dom.getName() );
-
-    } //-- void writeDomToSerializer( org.apache.maven.api.xml.XmlNode, XmlSerializer )
-
-
-#foreach ( $class in $model.allClasses )
- #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-  #set ( $classUcapName = $Helper.capitalise( $class.name ) )
-  #set ( $classLcapName = $Helper.uncapitalise( $class.name ) )
-  #set ( $allFields = $Helper.xmlFields( $class ) )
-    private void write${classUcapName}( String tagName, ${classUcapName} ${classLcapName}, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( ${classLcapName} != null )
-        {
-  #if ( $class == $root )
-            if ( this.fileComment != null )
-            {
-                serializer.comment(this.fileComment);
-            }
-            serializer.setPrefix( "", "http://maven.apache.org/POM/4.0.0" );
-            serializer.setPrefix( "xsi", "http://www.w3.org/2001/XMLSchema-instance" );
-            serializer.startTag( NAMESPACE, tagName );
-            serializer.attribute( "", "xsi:schemaLocation", "http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" );
-  #else
-            serializer.startTag( NAMESPACE, tagName );
-  #end
-  #foreach ( $field in $allFields )
-    #if ( $Helper.xmlFieldMetadata( $field ).attribute )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-      #if ( $field.type == "String" )
-            writeAttr( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #else
-        // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    #end
-  #end
-  #foreach ( $field in $allFields )
-    #if ( ! $Helper.xmlFieldMetadata( $field ).attribute && ! $Helper.xmlFieldMetadata( $field ).transient )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #if ( ! $fieldTagName )
-        #set ( $fieldTagName = $field.name )
-      #end
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-      #set ( $def = ${field.defaultValue} )
-      #if ( $field.type == "String" )
-        #if ( ! $def )
-            writeTag( "$fieldTagName", null, ${classLcapName}.get${fieldCapName}(), serializer );
-        #else
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.get${fieldCapName}(), serializer );
-        #end
-      #elseif ( $field.type == "boolean" || $field.type == "Boolean" )
-        #if ( ${def} == "true" )
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.is${fieldCapName}() ? null : "false", serializer );
-        #else
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.is${fieldCapName}() ? "true" : null, serializer );
-        #end
-      #elseif ( $field.type == "int" )
-            writeTag( "$fieldTagName", "${def}", Integer.toString( ${classLcapName}.get${fieldCapName}() ), serializer );
-      #elseif ( $field.type == "DOM" )
-            writeDom( ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-        #set( $singularField = ${Helper.singular($fieldTagName)} )
-            writeList( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer, t -> writeTag( "$singularField", "${def}", t, serializer ) );
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-            writeProperties( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.to && $field.multiplicity == "1" )
-            write${field.to}( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.to && $field.multiplicity == "*" )
-        #set( $singularField = ${Helper.singular($fieldTagName)} )
-            writeList( "$fieldTagName", $Helper.isFlatItems($field), ${classLcapName}.get${fieldCapName}(), serializer, t -> write${field.to}( "$singularField", t, serializer ) );
-      #else
-            // TODO: name=${field.name} type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    #end
-  #end
-            serializer.endTag( NAMESPACE, tagName );
-        }
-    }
-
- #end
-#end
-    @FunctionalInterface
-    private interface ElementWriter<T>
-    {
-        public void write( T t ) throws IOException;
-    }
-
-    private <T> void writeList( String tagName, List<T> list, XmlSerializer serializer, ElementWriter<T> writer )
-        throws IOException
-    {
-        writeList( tagName, false, list, serializer, writer );
-    }
-
-    private <T> void writeList( String tagName, boolean flat, List<T> list, XmlSerializer serializer, ElementWriter<T> writer )
-        throws IOException
-    {
-        if ( list != null && !list.isEmpty() )
-        {
-            if ( !flat )
-            {
-                serializer.startTag( NAMESPACE, tagName );
-            }
-            for ( T t : list )
-            {
-                writer.write( t );
-            }
-            if ( !flat )
-            {
-                serializer.endTag( NAMESPACE, tagName );
-            }
-        }
-    }
-
-    private <T> void writeProperties( String tagName, Map<String, String> props, XmlSerializer serializer )
-            throws IOException
-    {
-        if ( props != null && !props.isEmpty() )
-        {
-            serializer.startTag( NAMESPACE, tagName );
-            for ( Map.Entry<String, String> entry : props.entrySet() )
-            {
-                writeTag( entry.getKey(), null, entry.getValue(), serializer );
-            }
-            serializer.endTag( NAMESPACE, tagName );
-        }
-    }
-
-    private void writeDom( XmlNode dom, XmlSerializer serializer )
-            throws IOException
-    {
-        if ( dom != null )
-        {
-            serializer.startTag( NAMESPACE, dom.getName() );
-            for ( Map.Entry<String, String> attr : dom.getAttributes().entrySet() )
-            {
-                serializer.attribute( NAMESPACE, attr.getKey(), attr.getValue() );
-            }
-            for ( XmlNode child : dom.getChildren() )
-            {
-                writeDom( child, serializer );
-            }
-            String value = dom.getValue();
-            if ( value != null )
-            {
-                serializer.text( value );
-            }
-            serializer.endTag( NAMESPACE, dom.getName() );
-        }
-    }
-
-    private void writeTag( String tagName, String defaultValue, String value, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( value != null && !Objects.equals( defaultValue, value ) )
-        {
-            serializer.startTag( NAMESPACE, tagName ).text( value ).endTag( NAMESPACE, tagName );
-        }
-    }
-
-    private void writeAttr( String attrName, String value, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( value != null )
-        {
-            serializer.attribute( NAMESPACE, attrName, value );
-        }
-    }
-
-}
diff --git a/maven-plugin-api/pom.xml b/maven-plugin-api/pom.xml
index 1294bcb7c7e1..420df66d1ea8 100644
--- a/maven-plugin-api/pom.xml
+++ b/maven-plugin-api/pom.xml
@@ -60,6 +60,7 @@ under the License.
         <groupId>org.codehaus.modello</groupId>
         <artifactId>modello-maven-plugin</artifactId>
         <configuration>
+          <velocityBasedir>${project.basedir}/../src/mdo</velocityBasedir>
           <models>
             <model>src/main/mdo/lifecycle.mdo</model>
           </models>
@@ -74,9 +75,9 @@ under the License.
             <phase>generate-sources</phase>
             <configuration>
               <templates>
-                <template>src/main/mdo/model.vm</template>
-                <template>src/main/mdo/reader.vm</template>
-                <template>src/main/mdo/writer.vm</template>
+                <template>model.vm</template>
+                <template>reader.vm</template>
+                <template>writer.vm</template>
               </templates>
               <params>
                 <param>packageModelV3=org.apache.maven.plugin.lifecycle</param>
diff --git a/maven-plugin-api/src/main/mdo/common.vm b/maven-plugin-api/src/main/mdo/common.vm
deleted file mode 100644
index aa3d17a0398e..000000000000
--- a/maven-plugin-api/src/main/mdo/common.vm
+++ /dev/null
@@ -1,21 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-##
-## Nothing special to do here
-##
\ No newline at end of file
diff --git a/maven-plugin-api/src/main/mdo/merger.vm b/maven-plugin-api/src/main/mdo/merger.vm
deleted file mode 100644
index 98b04d4627b7..000000000000
--- a/maven-plugin-api/src/main/mdo/merger.vm
+++ /dev/null
@@ -1,380 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Merger" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.ObjectStreamException;
-import java.util.AbstractList;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Properties;
-import java.util.Objects;
-import java.util.function.BinaryOperator;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.api.xml.XmlNode;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.Name};
-#end
-
-@Generated
-public class ${className}
-{
-
-    /**
-     * Merges the specified source object into the given target object.
-     *
-     * @param target The target object whose existing contents should be merged with the source, must not be
-     *            <code>null</code>.
-     * @param source The (read-only) source object that should be merged into the target object, may be
-     *            <code>null</code>.
-     * @param sourceDominant A flag indicating whether either the target object or the source object provides the
-     *            dominant data.
-     * @param hints A set of key-value pairs that customized merger implementations can use to carry domain-specific
-     *            information along, may be <code>null</code>.
-     */
-    public ${root.name} merge( ${root.name} target, ${root.name} source, boolean sourceDominant, Map<?, ?> hints )
-    {
-        Objects.requireNonNull( target, "target cannot be null" );
-        if ( source == null )
-        {
-            return target;
-        }
-        Map<Object, Object> context = new HashMap<>();
-        if ( hints != null )
-        {
-            context.putAll( hints );
-        }
-        return merge${root.name}( target, source, sourceDominant, context );
-    }
-
-#foreach ( $class in $model.allClasses )
-  #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-    #set ( $ancestors = $Helper.ancestors( $class ) )
-    #set ( $allFields = [] )
-    #foreach ( $cl in $ancestors )
-      #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-    #end
-    protected ${class.name} merge${class.name}( ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-        ${class.name}.Builder builder = ${class.name}.newBuilder( target );
-        merge${class.name}( builder, target, source, sourceDominant, context );
-        return builder.build();
-    }
-
-    protected void merge${class.name}( ${class.name}.Builder builder, ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-    #if ( $class.superClass )
-        merge${class.superClass}( builder, target ,source, sourceDominant, context );
-    #end
-    #foreach ( $field in $class.getFields($version) )
-        merge${field.modelClass.name}_${Helper.capitalise($field.name)}( builder, target, source, sourceDominant, context );
-    #end
-    }
-
-    #foreach ( $field in $allFields )
-      #set ( $capField = ${Helper.capitalise($field.name)} )
-    protected void merge${class.name}_${capField}( ${class.name}.Builder builder, ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-      #if ( $field.type == "String" )
-        String src = source.get${capField}();
-        String tgt = target.get${capField}();
-        if ( src != null && ( sourceDominant || tgt == null ) )
-        {
-            builder.${field.name}( src );
-        #if ( $locationTracking )
-            builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-        }
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-        builder.${field.name}( merge( target.get${capField}(), source.get${capField}(), sourceDominant, e -> e ) );
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-        Properties src = source.get${capField}();
-        if ( !src.isEmpty() )
-        {
-            Properties tgt = target.get${capField}();
-            if ( tgt.isEmpty() )
-            {
-                builder.${field.name}( src );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-            }
-            else
-            {
-                Properties merged = new Properties();
-                merged.putAll( sourceDominant ? target.get${capField}() : source.get${capField}() );
-                merged.putAll( sourceDominant ? source.get${capField}() : target.get${capField}() );
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", InputLocation.merge( target.getLocation( "${field.name}" ), source.getLocation( "${field.name}" ), sourceDominant ) );
-        #end
-            }
-        }
-      #elseif ( $field.to && $field.multiplicity == "1" )
-        ${field.to} src = source.get${capField}();
-        if ( src != null )
-        {
-            ${field.to} tgt = target.get${capField}();
-            if ( tgt == null )
-            {
-                tgt = ${field.to}.newInstance( false );
-            }
-            ${field.to} merged = merge${field.to}( tgt, src, sourceDominant, context );
-            if ( merged == src )
-            {
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-            }
-            else if ( merged != tgt )
-            {
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", InputLocation.merge( target.getLocation( "${field.name}" ), source.getLocation( "${field.name}" ), sourceDominant ) );
-        #end
-            }
-        }
-      #elseif ( $field.to && $field.multiplicity == "*" )
-        builder.${field.name}( merge( target.get${capField}(), source.get${capField}(), sourceDominant, get${field.to}Key() ) );
-      #elseif ( $field.type == "DOM" )
-        XmlNode src = source.getConfiguration();
-        if ( src != null )
-        {
-            XmlNode tgt = target.getConfiguration();
-            if ( tgt == null )
-            {
-                builder.configuration( src );
-            }
-            else if ( sourceDominant )
-            {
-                builder.configuration( src.merge( tgt ) );
-            }
-            else
-            {
-                builder.configuration( tgt.merge( src ) );
-            }
-        }
-      #elseif ( $field.type == "boolean" )
-        if ( sourceDominant )
-        {
-            builder.${field.name}( source.is${capField}() );
-        }
-      #elseif ( $field.type == "int" || $field.type == "java.nio.file.Path" )
-        if ( sourceDominant )
-        {
-            builder.${field.name}( source.get${capField}() );
-        }
-      #else
-        // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    }
-    #end
-
-  #end
-#end
-
-#foreach ( $class in $model.allClasses )
-  #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-    protected KeyComputer<${class.name}> get${class.name}Key()
-    {
-        return v -> v;
-    }
-  #end
-#end
-
-    /**
-     * Use to compute keys for data structures
-     * @param <T> the data structure type
-     */
-    @FunctionalInterface
-    public interface KeyComputer<T> extends Function<T, Object>
-    {
-    }
-
-    /**
-     * Merge two lists
-     */
-    public static <T> List<T> merge( List<T> tgt, List<T> src, boolean sourceDominant, KeyComputer<T> computer )
-    {
-        return merge( tgt, src, computer, ( t, s ) -> sourceDominant ? s : t );
-    }
-
-    public static <T> List<T> merge( List<T> tgt, List<T> src, KeyComputer<T> computer, BinaryOperator<T> remapping )
-    {
-        if ( src.isEmpty() )
-        {
-            return tgt;
-        }
-
-        MergingList<T> list;
-        if ( tgt instanceof MergingList )
-        {
-            list = (MergingList<T>) tgt;
-        }
-        else
-        {
-            list = new MergingList<>( computer, src.size() + tgt.size() );
-            list.mergeAll( tgt, ( t, s ) -> s );
-        }
-
-        list.mergeAll( src, remapping );
-        return list;
-    }
-
-    /**
-     * Merging list
-     * @param <V>
-     */
-    private static class MergingList<V> extends AbstractList<V> implements java.io.Serializable
-    {
-
-        private final KeyComputer<V> keyComputer;
-        private Map<Object, V> map;
-        private List<V> list;
-
-        MergingList( KeyComputer<V> keyComputer, int initialCapacity )
-        {
-            this.map = new LinkedHashMap<>( initialCapacity );
-            this.keyComputer = keyComputer;
-        }
-
-        Object writeReplace() throws ObjectStreamException
-        {
-            return new ArrayList<>( this );
-        }
-
-        @Override
-        public Iterator<V> iterator()
-        {
-            if ( map != null )
-            {
-                return map.values().iterator();
-            }
-            else
-            {
-                return list.iterator();
-            }
-        }
-
-        void mergeAll( Collection<V> vs, BinaryOperator<V> remapping )
-        {
-            if ( map == null )
-            {
-                map = list.stream().collect( Collectors.toMap( keyComputer,
-                                                               Function.identity(),
-                                                               null,
-                                                               LinkedHashMap::new ) );
-
-                list = null;
-            }
-
-            if ( vs instanceof MergingList && ( (MergingList<V>) vs ).map != null )
-            {
-                for ( Map.Entry<Object, V> e : ( (MergingList<V>) vs ).map.entrySet() )
-                {
-                    Object key = e.getKey();
-                    V v = e.getValue();
-                    map.merge( key, v, remapping );
-                }
-            }
-            else
-            {
-                for ( V v : vs )
-                {
-                    Object key = keyComputer.apply( v );
-
-                    map.merge( key, v, remapping );
-                }
-            }
-        }
-
-        @Override
-        public boolean contains( Object o )
-        {
-            if ( map != null )
-            {
-                return map.containsValue( o );
-            }
-            else
-            {
-                return list.contains( o );
-            }
-        }
-
-        private List<V> asList()
-        {
-            if ( list == null )
-            {
-                list = new ArrayList<>( map.values() );
-                map = null;
-            }
-            return list;
-        }
-
-        @Override
-        public void add( int index, V element )
-        {
-            asList().add( index, element );
-        }
-
-        @Override
-        public V remove( int index )
-        {
-            return asList().remove( index );
-        }
-
-        @Override
-        public V get( int index )
-        {
-            return asList().get( index );
-        }
-
-        @Override
-        public int size()
-        {
-            if ( map != null )
-            {
-                return map.size();
-            }
-            else
-            {
-                return list.size();
-            }
-        }
-    }
-}
diff --git a/maven-plugin-api/src/main/mdo/model.vm b/maven-plugin-api/src/main/mdo/model.vm
deleted file mode 100644
index 61d77726b755..000000000000
--- a/maven-plugin-api/src/main/mdo/model.vm
+++ /dev/null
@@ -1,516 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageModelV4}" )
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#foreach ( $class in $model.allClasses )
-  #set ( $ancestors = $Helper.ancestors( $class ) )
-  #set ( $allFields = [] )
-  #set ( $inheritedFields = [] )
-  #foreach ( $cl in $ancestors )
-    #if ( $cl != $class )
-      #set ( $dummy = $inheritedFields.addAll( $cl.getFields($version) ) )
-    #end
-    #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-  #end
-  #set ( $className = "${class.name}" )
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-  #if ( $class.name != "InputLocation" && $class.name != "InputSource" )
-    #set ( $types = { } )
-    #set ( $imports = $class.getClass().forName("java.util.TreeSet").newInstance() )
-    #set ( $dummy = $imports.add( "java.io.Serializable" ) )
-    #set ( $dummy = $imports.add( "java.util.Collections" ) )
-    #set ( $dummy = $imports.add( "java.util.HashMap" ) )
-    #set ( $dummy = $imports.add( "java.util.Map" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Generated" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Immutable" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Nonnull" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.NotThreadSafe" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.ThreadSafe" ) )
-    #foreach ( $field in $allFields )
-      #if ( $field.type == "java.util.List" )
-          #set ( $dummy = $imports.add( "java.util.ArrayList" ) )
-          #set ( $dummy = $imports.add( "java.util.Collection" ) )
-          #set ( $dummy = $imports.add( "java.util.List" ) )
-          #set ( $dummy = $types.put( $field, "List<" + $field.to + ">" ) )
-      #elseif ( $field.type == "DOM" )
-        #set ( $dummy = $imports.add( "org.apache.maven.api.xml.XmlNode" ) )
-        #set ( $dummy = $types.put( $field, "XmlNode" ) )
-      #else
-        #set ( $fieldType = ${types.getOrDefault($field.type,$field.type)} )
-        #set ( $idx = $fieldType.lastIndexOf('.') )
-        #if ( $idx > 0 )
-          #set ( $dummy = $imports.add( $fieldType ) )
-          #set ( $dummy = $types.put( $fieldType, $fieldType.substring( $idx + 1 ) ) )
-        #end
-      #end
-    #end
-    #set ( $eq = "" )
-    #set ( $hc = "" )
-    #foreach ( $field in $allFields )
-      #if ( $field.identifier )
-        #set ( $dummy = $imports.add( "java.util.Objects" ) )
-        #set ( $dummy = $identifiers.add( $field ) )
-        #if ( $eq == "" )
-          #set ( $eq = "Objects.equals( this.${field.name}, that.${field.name} )" )
-        #else
-          #set ( $eq = "$eq && Objects.equals( this.${field.name}, that.${field.name} )" )
-        #end
-        #if ( $hc == "" )
-          #set ( $hc = "${field.name}" )
-        #else
-          #set ( $hc = "$hc, this.${field.name}" )
-        #end
-      #end
-    #end
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-    #foreach ( $imp in $imports )
-import $imp;
-    #end
-
-/**
-    #foreach ( $line in ${class.description.trim().split("\n")} )
- * ${line.trim()}
-    #end
- */
-@Generated @ThreadSafe @Immutable
-public class ${class.name}
-    #if ( $class.superClass )
-    extends ${class.superClass}
-    #end
-    #if ( $locationTracking )
-    implements Serializable, InputLocationTracker
-    #else
-    implements Serializable
-    #end
-{
-    #if ( $class == $root )
-    final String modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-    /**
-      #foreach ( $line in ${field.description.trim().split("\n")} )
-     * ${line.trim()}
-      #end
-     */
-    final ${type} $field.name;
-    #end
-    #if ( $locationTracking )
-      #if ( ! $class.superClass )
-    /** Location of the xml element for this object. */
-    final InputLocation location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-    /** Location of the xml element for the field ${field.name}. */
-    final InputLocation ${field.name}Location;
-      #end
-      #if ( ! $class.superClass )
-    /** Other locations */
-    final Map<Object, InputLocation> locations;
-      #end
-    #end
-
-    /**
-      * Constructor for this class, package protected.
-      * @see Builder#build()
-      */
-    ${class.name}(
-    #if ( $class == $root )
-        String modelEncoding,
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $sep = "#if(${locationTracking}||$field!=${allFields[${allFields.size()} - 1]}),#end" )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-        $type $field.name${sep}
-    #end
-    #if ( $locationTracking )
-        Map<Object, InputLocation> locations,
-        InputLocation location,
-      #foreach ( $field in $allFields )
-        #set ( $sep = "#if(${locationTracking}&&$field!=${allFields[${allFields.size()} - 1]}),#end" )
-        InputLocation ${field.name}Location${sep}
-      #end
-    #end
-    )
-    {
-    #if ( $class.superClass )
-        super(
-      #foreach ( $field in $inheritedFields )
-        #set ( $sep = "#if(${locationTracking}||$field!=${inheritedFields[${inheritedFields.size()} - 1]}),#end" )
-            ${field.name}${sep}
-      #end
-      #if ( $locationTracking )
-            locations,
-            location,
-        #foreach ( $field in $inheritedFields )
-          #set ( $sep = "#if(${locationTracking}&&$field!=${inheritedFields[${inheritedFields.size()} - 1]}),#end" )
-            ${field.name}Location${sep}
-        #end
-      #end
-        );
-    #end
-    #if ( $class == $root )
-        this.modelEncoding = modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #if ( $field.type == "java.util.List" || $field.type == "java.util.Properties" || $field.type == "java.util.Map" )
-        this.${field.name} = ImmutableCollections.copy( ${field.name} );
-      #else
-        this.${field.name} = ${field.name};
-      #end
-    #end
-    #if ( $locationTracking )
-      #if ( ! $class.superClass )
-        this.locations = ImmutableCollections.copy( locations );
-        this.location = location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-        this.${field.name}Location = ${field.name}Location;
-      #end
-    #end
-    }
-
-    #if ( ! $eq.empty )
-    @Override
-    public boolean equals( Object o )
-    {
-        if ( this == o )
-        {
-            return true;
-        }
-        if ( o == null || !( o instanceof ${class.name} ) )
-        {
-            return false;
-        }
-        ${class.name} that = ( ${class.name} ) o;
-        return ${eq};
-    }
-
-    @Override
-    public int hashCode()
-    {
-        return Objects.hash( ${hc} );
-    }
-
-    #end
-    #if ( $class == $root )
-    public String getModelEncoding()
-    {
-        return modelEncoding;
-    }
-
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $cap = $Helper.capitalise( $field.name ) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type == "boolean" || $type == "Boolean" )
-        #set ( $pfx = "is" )
-      #else
-        #set ( $pfx = "get" )
-      #end
-    /**
-      #set ( $desc = ${field.description.trim()} )
-      #foreach ( $line in ${desc.split("\n")} )
-     * ${line.trim()}
-      #end
-     */
-      #if ( $field.type == "java.util.List" || $field.type == "java.util.Properties" )
-    @Nonnull
-      #end
-    public ${type} ${pfx}${cap}()
-    {
-        return this.${field.name};
-    }
-
-    #end
-    #if ( $locationTracking )
-    /**
-     * Gets the location of the specified field in the input source.
-     */
-    public InputLocation getLocation( Object key )
-    {
-        if ( key instanceof String )
-        {
-            switch ( ( String ) key )
-            {
-      #if ( ! $class.superClass )
-                case "":
-                    return location;
-      #end
-      #foreach ( $field in $class.getFields($version) )
-                case "${field.name}":
-                    return ${field.name}Location;
-      #end
-            }
-        }
-      #if ( $class.superClass )
-        return super.getLocation( key );
-      #else
-        return locations != null ? locations.get( key ) : null;
-      #end
-    }
-
-    #end
-    /**
-     * Creates a new builder with this object as the basis.
-     */
-    @Nonnull
-    public Builder with()
-    {
-        return newBuilder( this );
-    }
-    #foreach ( $field in $allFields )
-      #set ( $cap = $Helper.capitalise( $field.name ) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-    /** Creates a new ${class.name} instance using the specified ${field.name}. */
-    @Nonnull
-    public ${class.name} with${cap}( $type $field.name )
-    {
-        return with().${field.name}( $field.name ).build();
-    }
-    #end
-
-    /**
-     * Creates a new ${class.name} instance.
-     * Equivalent to {@code newInstance( true )}.
-     * @see #newInstance(boolean)
-     */
-    @Nonnull
-    public static ${class.name} newInstance()
-    {
-        return newInstance( true );
-    }
-
-    /**
-     * Creates a new ${class.name} instance using default values or not.
-     * Equivalent to {@code newBuilder( withDefaults ).build()}.
-     */
-    @Nonnull
-    public static ${class.name} newInstance( boolean withDefaults )
-    {
-        return newBuilder( withDefaults ).build();
-    }
-
-    /**
-     * Creates a new ${class.name} builder instance.
-     * Equivalent to {@code newBuilder( true )}.
-     * @see #newBuilder(boolean)
-     */
-    @Nonnull
-    public static Builder newBuilder()
-    {
-        return newBuilder( true );
-    }
-
-    /**
-     * Creates a new ${class.name} builder instance using default values or not.
-     */
-    @Nonnull
-    public static Builder newBuilder( boolean withDefaults )
-    {
-        return new Builder( withDefaults );
-    }
-
-    /**
-     * Creates a new ${class.name} builder instance using the specified object as a basis.
-     * Equivalent to {@code newBuilder( from, false )}.
-     */
-    @Nonnull
-    public static Builder newBuilder( ${class.name} from )
-    {
-        return newBuilder( from, false );
-    }
-
-    /**
-     * Creates a new ${class.name} builder instance using the specified object as a basis.
-     */
-    @Nonnull
-    public static Builder newBuilder( ${class.name} from, boolean forceCopy )
-    {
-        return new Builder( from, forceCopy );
-    }
-
-    /**
-     * Builder class used to create ${class.name} instances.
-     * @see #with()
-     * @see #newBuilder()
-     */
-    @NotThreadSafe
-    public static class Builder
-    #if ( $class.superClass )
-        extends ${class.superClass}.Builder
-    #end
-    {
-        ${class.name} base;
-    #if ( $class == $root )
-        String modelEncoding;
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-      #if ( $type == 'boolean' )
-        Boolean ${field.name};
-      #elseif ( $type == 'int' )
-        Integer ${field.name};
-      #else
-        ${type} ${field.name};
-    #end
-    #end
-    #if ( ! $class.superClass && $locationTracking )
-        Map<Object, InputLocation> locations;
-    #end
-
-        Builder( boolean withDefaults )
-        {
-    #if ( $class.superClass )
-            super( withDefaults );
-    #end
-            if ( withDefaults )
-            {
-    #foreach ( $field in $class.getFields($version) )
-      #if ( $field.defaultValue )
-        #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-        #if ( $field.type == "String" )
-                this.${field.name} = "${field.defaultValue}";
-        #elseif ( $field.type != "java.util.List" && $field.type != "java.util.Properties" )
-                this.${field.name} = ${field.defaultValue};
-        #end
-      #end
-    #end
-            }
-        }
-
-        Builder( ${class.name} base, boolean forceCopy )
-        {
-    #if ( $class.superClass )
-            super( base, forceCopy );
-    #end
-            if ( forceCopy )
-            {
-    #foreach ( $field in $class.getFields($version) )
-                this.${field.name} = base.${field.name};
-    #end
-            }
-            else
-            {
-                this.base = base;
-            }
-        }
-
-    #if ( $class == $root )
-        @Nonnull
-        public Builder modelEncoding( String modelEncoding )
-        {
-            this.modelEncoding = modelEncoding;
-            return this;
-        }
-
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type.startsWith("List<") )
-        #set ( $type = ${type.replace('List<','Collection<')} )
-      #end
-        @Nonnull
-        public Builder ${field.name}( ${type} ${field.name} )
-        {
-            this.${field.name} = ${field.name};
-            return this;
-        }
-
-    #end
-
-    #if ( $locationTracking )
-        @Nonnull
-        public Builder location( Object key, InputLocation location )
-        {
-            if ( location != null )
-            {
-                if ( this.locations == null )
-                {
-                    this.locations = new HashMap<>();
-                }
-                this.locations.put( key, location );
-            }
-            return this;
-        }
-
-    #end
-        @Nonnull
-        public ${class.name} build()
-        {
-            if ( base != null
-    #foreach ( $field in $allFields )
-                    && ( ${field.name} == null || ${field.name} == base.${field.name} )
-    #end
-            )
-            {
-                return base;
-            }
-    #if ( $locationTracking )
-            Map<Object, InputLocation> locations = new HashMap<>( this.locations != null ? this.locations : ( base != null ? base.locations : Collections.emptyMap() ) );
-            InputLocation location = locations.remove( "" );
-      #foreach ( $field in $allFields )
-            InputLocation ${field.name}Location = locations.remove( "${field.name}" );
-      #end
-    #end
-            return new ${class.name}(
-    #if ( $class == $root )
-                modelEncoding != null ? modelEncoding : ( base != null ? base.modelEncoding : "UTF-8" ),
-    #end
-    #foreach ( $field in $allFields )
-      #set ( $sep = "#if(${locationTracking}||$field!=${allFields[${allFields.size()} - 1]}),#end" )
-      #if ( $field.type == "boolean" || $field.type == "int" )
-                ${field.name} != null ? ${field.name} : ( base != null ? base.${field.name} : ${field.defaultValue} )${sep}
-      #else
-                ${field.name} != null ? ${field.name} : ( base != null ? base.${field.name} : null )${sep}
-      #end
-    #end
-    #if ( $locationTracking )
-                locations,
-                location != null ? location : ( base != null ? base.location : null ),
-      #foreach ( $field in $allFields )
-        #set ( $sep = "#if(${locationTracking}&&$field!=${allFields[${allFields.size()} - 1]}),#end" )
-                ${field.name}Location != null ? ${field.name}Location : ( base != null ? base.${field.name}Location : null )${sep}
-      #end
-    #end
-            );
-        }
-    }
-
-    #foreach ( $cs in $class.getCodeSegments($version) )
-$cs.code
-    #end
-}
-  #end
-#end
diff --git a/maven-plugin-api/src/main/mdo/reader.vm b/maven-plugin-api/src/main/mdo/reader.vm
deleted file mode 100644
index 54b3882bbf2e..000000000000
--- a/maven-plugin-api/src/main/mdo/reader.vm
+++ /dev/null
@@ -1,899 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Xpp3Reader" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#set ( $rootXml = $Helper.xmlClassMetadata( $root ) )
-#set ( $rootTag = $rootXml.tagName )
-#set ( $rootUcapName = $Helper.capitalise( $root.name ) )
-#set ( $rootLcapName = $Helper.uncapitalise( $root.name ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.Reader;
-import java.text.DateFormat;
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Properties;
-import java.util.Set;
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.internal.xml.XmlNodeBuilder;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.name};
-#end
-import org.codehaus.plexus.util.ReaderFactory;
-import org.codehaus.plexus.util.xml.pull.EntityReplacementMap;
-import org.codehaus.plexus.util.xml.pull.MXParser;
-import org.codehaus.plexus.util.xml.pull.XmlPullParser;
-import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
-
-@Generated
-public class ${className}
-{
-    private boolean addDefaultEntities = true;
-
-    private final ContentTransformer contentTransformer;
-
-    public ${className}()
-    {
-        this( ( s, f ) -> s );
-    }
-
-    public ${className}( ContentTransformer contentTransformer )
-    {
-        this.contentTransformer = contentTransformer;
-    }
-
-    /**
-     * Method checkFieldWithDuplicate.
-     *
-     * @param parser a parser object.
-     * @param parsed a parsed object.
-     * @param alias a alias object.
-     * @param tagName a tagName object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return boolean
-     */
-    private boolean checkFieldWithDuplicate( XmlPullParser parser, String tagName, String alias, Set<String> parsed )
-        throws XmlPullParserException
-    {
-        if ( !( parser.getName().equals( tagName ) || parser.getName().equals( alias ) ) )
-        {
-            return false;
-        }
-        if ( !parsed.add( tagName ) )
-        {
-            throw new XmlPullParserException( "Duplicated tag: '" + tagName + "'", parser, null );
-        }
-        return true;
-    } //-- boolean checkFieldWithDuplicate( XmlPullParser, String, String, Set<String> )
-
-    /**
-     * Method checkUnknownAttribute.
-     *
-     * @param parser a parser object.
-     * @param strict a strict object.
-     * @param tagName a tagName object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @throws IOException IOException if any.
-     */
-    private void checkUnknownAttribute( XmlPullParser parser, String attribute, String tagName, boolean strict )
-        throws XmlPullParserException, IOException
-    {
-        // strictXmlAttributes = true for model: if strict == true, not only elements are checked but attributes too
-        if ( strict )
-        {
-            throw new XmlPullParserException( "Unknown attribute '" + attribute + "' for tag '" + tagName + "'", parser, null );
-        }
-    } //-- void checkUnknownAttribute( XmlPullParser, String, String, boolean )
-
-    /**
-     * Method checkUnknownElement.
-     *
-     * @param parser a parser object.
-     * @param strict a strict object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @throws IOException IOException if any.
-     */
-    private void checkUnknownElement( XmlPullParser parser, boolean strict )
-        throws XmlPullParserException, IOException
-    {
-        if ( strict )
-        {
-            throw new XmlPullParserException( "Unrecognised tag: '" + parser.getName() + "'", parser, null );
-        }
-
-        for ( int unrecognizedTagCount = 1; unrecognizedTagCount > 0; )
-        {
-            int eventType = parser.next();
-            if ( eventType == XmlPullParser.START_TAG )
-            {
-                unrecognizedTagCount++;
-            }
-            else if ( eventType == XmlPullParser.END_TAG )
-            {
-                unrecognizedTagCount--;
-            }
-        }
-    } //-- void checkUnknownElement( XmlPullParser, boolean )
-
-    /**
-     * Returns the state of the "add default entities" flag.
-     *
-     * @return boolean
-     */
-    public boolean getAddDefaultEntities()
-    {
-        return addDefaultEntities;
-    } //-- boolean getAddDefaultEntities()
-
-    /**
-     * Method getBooleanValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return boolean
-     */
-    private boolean getBooleanValue( String s, String attribute, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        return getBooleanValue( s, attribute, parser, null );
-    } //-- boolean getBooleanValue( String, String, XmlPullParser )
-
-    /**
-     * Method getBooleanValue.
-     *
-     * @param s a s object.
-     * @param defaultValue a defaultValue object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return boolean
-     */
-    private boolean getBooleanValue( String s, String attribute, XmlPullParser parser, String defaultValue )
-        throws XmlPullParserException
-    {
-        if ( s != null && s.length() != 0 )
-        {
-            return Boolean.valueOf( s ).booleanValue();
-        }
-        if ( defaultValue != null )
-        {
-            return Boolean.valueOf( defaultValue ).booleanValue();
-        }
-        return false;
-    } //-- boolean getBooleanValue( String, String, XmlPullParser, String )
-
-    /**
-     * Method getByteValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return byte
-     */
-    private byte getByteValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Byte.valueOf( s ).byteValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a byte", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- byte getByteValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getCharacterValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return char
-     */
-    private char getCharacterValue( String s, String attribute, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            return s.charAt( 0 );
-        }
-        return 0;
-    } //-- char getCharacterValue( String, String, XmlPullParser )
-
-    /**
-     * Method getDateValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return Date
-     */
-    private Date getDateValue( String s, String attribute, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        return getDateValue( s, attribute, null, parser );
-    } //-- Date getDateValue( String, String, XmlPullParser )
-
-    /**
-     * Method getDateValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param dateFormat a dateFormat object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return Date
-     */
-    private Date getDateValue( String s, String attribute, String dateFormat, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            String effectiveDateFormat = dateFormat;
-            if ( dateFormat == null )
-            {
-                effectiveDateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS";
-            }
-            if ( "long".equals( effectiveDateFormat ) )
-            {
-                try
-                {
-                    return new java.util.Date( Long.parseLong( s ) );
-                }
-                catch ( NumberFormatException e )
-                {
-                    throw new XmlPullParserException( e.getMessage(), parser, e );
-                }
-            }
-            else
-            {
-                try
-                {
-                    DateFormat dateParser = new java.text.SimpleDateFormat( effectiveDateFormat, java.util.Locale.US );
-                    return dateParser.parse( s );
-                }
-                catch ( java.text.ParseException e )
-                {
-                    throw new XmlPullParserException( e.getMessage(), parser, e );
-                }
-            }
-        }
-        return null;
-    } //-- Date getDateValue( String, String, String, XmlPullParser )
-
-    /**
-     * Method getDoubleValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return double
-     */
-    private double getDoubleValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Double.valueOf( s ).doubleValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a floating point number", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- double getDoubleValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getFloatValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return float
-     */
-    private float getFloatValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Float.valueOf( s ).floatValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a floating point number", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- float getFloatValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getIntegerValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return int
-     */
-    private int getIntegerValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        return getIntegerValue( s, attribute, parser, strict, 0 );
-    } //-- int getBooleanValue( String, String, XmlPullParser )
-
-    /**
-     * Method getIntegerValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return int
-     */
-    private int getIntegerValue( String s, String attribute, XmlPullParser parser, boolean strict, int defaultValue )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Integer.valueOf( s ).intValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be an integer", parser, nfe );
-                }
-            }
-        }
-        return defaultValue;
-    } //-- int getIntegerValue( String, String, XmlPullParser, boolean, int )
-
-    /**
-     * Method getLongValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return long
-     */
-    private long getLongValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Long.valueOf( s ).longValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a long integer", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- long getLongValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getRequiredAttributeValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return String
-     */
-    private String getRequiredAttributeValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s == null )
-        {
-            if ( strict )
-            {
-                throw new XmlPullParserException( "Missing required value for attribute '" + attribute + "'", parser, null );
-            }
-        }
-        return s;
-    } //-- String getRequiredAttributeValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getShortValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return short
-     */
-    private short getShortValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Short.valueOf( s ).shortValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a short integer", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- short getShortValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getTrimmedValue.
-     *
-     * @param s a s object.
-     * @return String
-     */
-    private String getTrimmedValue( String s )
-    {
-        if ( s != null )
-        {
-            s = s.trim();
-        }
-        return s;
-    } //-- String getTrimmedValue( String )
-
-    /**
-     * Method interpolatedTrimmed.
-     *
-     * @param value a value object.
-     * @param context a context object.
-     * @return String
-     */
-    private String interpolatedTrimmed( String value, String context )
-    {
-        return getTrimmedValue( contentTransformer.transform( value, context ) );
-    } //-- String interpolatedTrimmed( String, String )
-
-    /**
-     * Method nextTag.
-     *
-     * @param parser a parser object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return int
-     */
-    private int nextTag( XmlPullParser parser )
-        throws IOException, XmlPullParserException
-    {
-        int eventType = parser.next();
-        if ( eventType == XmlPullParser.TEXT )
-        {
-            eventType = parser.next();
-        }
-        if ( eventType != XmlPullParser.START_TAG && eventType != XmlPullParser.END_TAG )
-        {
-            throw new XmlPullParserException( "expected START_TAG or END_TAG not " + XmlPullParser.TYPES[eventType], parser, null );
-        }
-        return eventType;
-    } //-- int nextTag( XmlPullParser )
-
-    /**
-     * @see ReaderFactory#newXmlReader
-     *
-     * @param reader a reader object.
-     * @param strict a strict object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( Reader reader, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        XmlPullParser parser = addDefaultEntities ? new MXParser(EntityReplacementMap.defaultEntityReplacementMap) : new MXParser( );
-
-        parser.setInput( reader );
-
-
-        return read( parser, strict );
-    } //-- ${root.name} read( Reader, boolean )
-
-    /**
-     * @see ReaderFactory#newXmlReader
-     *
-     * @param reader a reader object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( Reader reader )
-        throws IOException, XmlPullParserException
-    {
-        return read( reader, true );
-    } //-- ${root.name} read( Reader )
-
-    /**
-     * Method read.
-     *
-     * @param in a in object.
-     * @param strict a strict object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( InputStream in, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        return read( ReaderFactory.newXmlReader( in ), strict );
-    } //-- ${root.name} read( InputStream, boolean )
-
-    /**
-     * Method read.
-     *
-     * @param in a in object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( InputStream in )
-        throws IOException, XmlPullParserException
-    {
-        return read( ReaderFactory.newXmlReader( in ) );
-    } //-- ${root.name} read( InputStream )
-
-    /**
-     * Method read.
-     *
-     * @param parser a parser object.
-     * @param strict a strict object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( XmlPullParser parser, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        $rootUcapName $rootLcapName = null;
-        int eventType = parser.getEventType();
-        boolean parsed = false;
-        while ( eventType != XmlPullParser.END_DOCUMENT )
-        {
-            if ( eventType == XmlPullParser.START_TAG )
-            {
-                if ( strict && ! "${rootTag}".equals( parser.getName() ) )
-                {
-                    throw new XmlPullParserException( "Expected root element '${rootTag}' but found '" + parser.getName() + "'", parser, null );
-                }
-                else if ( parsed )
-                {
-                    // fallback, already expected a XmlPullParserException due to invalid XML
-                    throw new XmlPullParserException( "Duplicated tag: '${rootTag}'", parser, null );
-                }
-                $rootLcapName = parse${rootUcapName}( parser, strict );
-                parsed = true;
-            }
-            eventType = parser.next();
-        }
-        if ( parsed )
-        {
-            return $rootLcapName;
-        }
-        throw new XmlPullParserException( "Expected root element '${rootTag}' but found no element at all: invalid XML document", parser, null );
-    } //-- ${root.name} read( XmlPullParser, boolean )
-
-#foreach ( $class in $model.allClasses )
- #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-  #set ( $classUcapName = $Helper.capitalise( $class.name ) )
-  #set ( $classLcapName = $Helper.uncapitalise( $class.name ) )
-  #set ( $ancestors = $Helper.ancestors( $class ) )
-  #set ( $allFields = [] )
-  #foreach ( $cl in $ancestors )
-    #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-  #end
-    private ${classUcapName} parse${classUcapName}( XmlPullParser parser, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        String tagName = parser.getName();
-        ${classUcapName}.Builder ${classLcapName} = ${classUcapName}.newBuilder( true );
-        for ( int i = parser.getAttributeCount() - 1; i >= 0; i-- )
-        {
-            String name = parser.getAttributeName( i );
-            String value = parser.getAttributeValue( i );
-            if ( name.indexOf( ':' ) >= 0 )
-            {
-                // just ignore attributes with non-default namespace (for example: xmlns:xsi)
-            }
-  #if ( $class == $root )
-            else if ( "xmlns".equals( name ) )
-            {
-                // ignore xmlns attribute in root class, which is a reserved attribute name
-            }
-  #end
-  #foreach ( $field in $allFields )
-    #if ( $Helper.xmlFieldMetadata( $field ).attribute )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-            else if ( "$fieldTagName".equals( name ) )
-            {
-      #if ( $field.type == "String" )
-                ${classLcapName}.${field.name}( interpolatedTrimmed( value, "$fieldTagName" ) );
-      #elseif ( $field.type == "boolean" || $field.type == "Boolean" )
-                ${classLcapName}.${field.name}( getBooleanValue( interpolatedTrimmed( value, "$fieldTagName" ), "$fieldTagName", parser, "${field.defaultValue}" ) );
-      #else
-                // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-            }
-    #end
-  #end
-            else
-            {
-                checkUnknownAttribute( parser, name, tagName, strict );
-            }
-        }
-        Set<String> parsed = new HashSet<>();
-  #foreach ( $field in $allFields )
-    #if ( $Helper.isFlatItems( $field ) )
-        List<$field.to> ${field.name} = new ArrayList<>();
-    #end
-  #end
-        while ( ( strict ? parser.nextTag() : nextTag( parser ) ) == XmlPullParser.START_TAG )
-        {
-            String childName = checkDuplicate( parser.getName(), parser, parsed );
-            switch ( childName )
-            {
-  #set( $ift = "if" )
-  #foreach ( $field in $allFields )
-    #if ( ! $Helper.xmlFieldMetadata( $field ).attribute && ! $Helper.xmlFieldMetadata( $field ).transient )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #if ( ! $fieldTagName )
-        #set ( $fieldTagName = $field.name )
-      #end
-      #if ( $Helper.isFlatItems( $field ) )
-        #set ( $fieldTagName = $Helper.singular( $fieldTagName ) )
-      #end
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-                case "${fieldTagName}":
-                {
-      #if ( $field.type == "String" )
-                    ${classLcapName}.${field.name}( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ) );
-                    break;
-      #elseif ( $field.type == "boolean" || $field.type == "Boolean" )
-                    ${classLcapName}.${field.name}( getBooleanValue( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ), "${fieldTagName}", parser, "${field.defaultValue}" ) );
-                    break;
-      #elseif ( $field.type == "int" )
-                    ${classLcapName}.${field.name}( getIntegerValue( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ), "${fieldTagName}", parser, strict, ${field.defaultValue} ) );
-                    break;
-      #elseif ( $field.type == "DOM" )
-                    ${classLcapName}.${field.name}( XmlNodeBuilder.build( parser, true ) );
-                    break;
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-                    List<String> ${field.name} = new ArrayList<>();
-                    while ( parser.nextTag() == XmlPullParser.START_TAG )
-                    {
-                        if ( "${Helper.singular($fieldTagName)}".equals( parser.getName() ) )
-                        {
-                            ${field.name}.add( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ) );
-                        }
-                        else
-                        {
-                            checkUnknownElement( parser, strict );
-                        }
-                    }
-                    ${classLcapName}.${field.name}( ${field.name} );
-                    break;
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-                    Properties ${field.name} = new Properties();
-                    while ( parser.nextTag() == XmlPullParser.START_TAG )
-                    {
-                        String key = parser.getName();
-                        String value = parser.nextText().trim();
-                        ${field.name}.put( key, value );
-                    }
-                    ${classLcapName}.${field.name}( ${field.name} );
-                    break;
-      #elseif ( $field.to && $field.multiplicity == "1" )
-                    ${classLcapName}.${field.name}( parse${field.toClass.name}( parser, strict ) );
-                    break;
-      #elseif ( $field.to && $field.multiplicity == "*" && $Helper.isFlatItems( $field ) )
-                    ${field.name}.add( parse${field.toClass.name}( parser, strict ) );
-                    break;
-      #elseif ( $field.to && $field.multiplicity == "*" )
-                    List<$field.to> ${field.name} = new ArrayList<>();
-                    while ( parser.nextTag() == XmlPullParser.START_TAG )
-                    {
-                        if ( "${Helper.singular($fieldTagName)}".equals( parser.getName() ) )
-                        {
-                            ${field.name}.add( parse${field.toClass.name}( parser, strict ) );
-                        }
-                        else
-                        {
-                            checkUnknownElement( parser, strict );
-                        }
-                    }
-                    ${classLcapName}.${field.name}( ${field.name} );
-                    break;
-      #else
-                    // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-                    break;
-      #end
-                }
-      #set( $ift = "else if" )
-    #end
-  #end
-                default:
-                {
-                    checkUnknownElement( parser, strict );
-                    break;
-                }
-            }
-        }
-  #foreach ( $field in $allFields )
-    #if ( $Helper.isFlatItems( $field ) )
-        ${classLcapName}.${field.name}( ${field.name} );
-    #end
-  #end
-  #if ( $class == $root )
-        ${classLcapName}.modelEncoding( parser.getInputEncoding() );
-  #end
-        return ${classLcapName}.build();
-    }
-
- #end
-#end
-
-    private String checkDuplicate( String tagName, XmlPullParser parser, Set<String> parsed )
-        throws XmlPullParserException
-    {
-#set( $aliases = { } )
-#set( $flats = { } )
-#foreach( $class in $model.allClasses )
-  #foreach ( $field in $class.getFields($version) )
-    #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-    #if ( ! $fieldTagName )
-      #set ( $fieldTagName = $field.name )
-    #end
-    #if ( $field.alias )
-      #set ( $dummy = $aliases.put( $field.alias, $fieldTagName ) )
-    #end
-    #if ( $Helper.isFlatItems( $field ) )
-      #set ( $fieldTagName = $Helper.singular($fieldTagName) )
-      #set ( $dummy = $flats.put( $fieldTagName, "" ) )
-    #end
-  #end
-#end
-#if ( ! ${aliases.isEmpty()} )
-        switch ( tagName )
-        {
-  #foreach( $entry in $aliases.entrySet() )
-            case "${entry.key}":
-                tagName = "${entry.value}";
-  #end
-        }
-#end
-#if ( ! ${flats.isEmpty()} )
-        switch ( tagName )
-        {
-  #foreach( $entry in $flats.entrySet() )
-            case "${entry.key}":
-  #end
-                break;
-            default:
-                if ( !parsed.add( tagName ) )
-                {
-                    throw new XmlPullParserException( "Duplicated tag: '" + tagName + "'", parser, null );
-                }
-        }
-#end
-        return tagName;
-    }
-
-    /**
-     * Sets the state of the "add default entities" flag.
-     *
-     * @param addDefaultEntities a addDefaultEntities object.
-     */
-    public void setAddDefaultEntities( boolean addDefaultEntities )
-    {
-        this.addDefaultEntities = addDefaultEntities;
-    } //-- void setAddDefaultEntities( boolean )
-
-    public static interface ContentTransformer
-    {
-        /**
-         * Interpolate the value read from the xpp3 document
-         * @param source The source value
-         * @param fieldName A description of the field being interpolated. The implementation may use this to
-         *                           log stuff.
-         * @return The interpolated value.
-         */
-        String transform( String source, String fieldName );
-    }
-
-}
diff --git a/maven-plugin-api/src/main/mdo/writer.vm b/maven-plugin-api/src/main/mdo/writer.vm
deleted file mode 100644
index 7c2f46e364a5..000000000000
--- a/maven-plugin-api/src/main/mdo/writer.vm
+++ /dev/null
@@ -1,331 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Xpp3Writer" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#set ( $rootXml = $Helper.xmlClassMetadata( $root ) )
-#set ( $rootTag = $rootXml.tagName )
-#set ( $rootUcapName = $Helper.capitalise( $root.name ) )
-#set ( $rootLcapName = $Helper.uncapitalise( $root.name ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.io.Reader;
-import java.io.Writer;
-import java.text.DateFormat;
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Properties;
-import java.util.Set;
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.api.xml.XmlNode;
-import org.apache.maven.internal.xml.XmlNodeBuilder;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.name};
-#end
-import org.codehaus.plexus.util.ReaderFactory;
-import org.codehaus.plexus.util.xml.pull.EntityReplacementMap;
-import org.codehaus.plexus.util.xml.pull.MXParser;
-import org.codehaus.plexus.util.xml.pull.MXSerializer;
-import org.codehaus.plexus.util.xml.pull.XmlPullParser;
-import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
-import org.codehaus.plexus.util.xml.pull.XmlSerializer;
-
-@Generated
-public class ${className}
-{
-      //--------------------------/
-     //- Class/Member Variables -/
-    //--------------------------/
-
-    /**
-     * Field NAMESPACE.
-     */
-    private static final String NAMESPACE = null;
-
-    /**
-     * Field fileComment.
-     */
-    private String fileComment = null;
-
-
-      //-----------/
-     //- Methods -/
-    //-----------/
-
-    /**
-     * Method setFileComment.
-     *
-     * @param fileComment a fileComment object.
-     */
-    public void setFileComment( String fileComment )
-    {
-        this.fileComment = fileComment;
-    } //-- void setFileComment( String )
-
-    /**
-     * Method write.
-     *
-     * @param writer a writer object
-     * @param ${rootLcapName} a ${root.name} object
-     * @throws java.io.IOException java.io.IOException if any.
-     */
-    public void write( Writer writer, ${root.name} ${rootLcapName} )
-        throws java.io.IOException
-    {
-        XmlSerializer serializer = new MXSerializer();
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-indentation", "  " );
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-line-separator", "\n" );
-        serializer.setOutput( writer );
-        serializer.startDocument( ${rootLcapName}.getModelEncoding(), null );
-        write${root.name}( "$rootTag", ${rootLcapName}, serializer );
-        serializer.endDocument();
-    } //-- void write( Writer, ${root.name} )
-
-    /**
-     * Method write.
-     *
-     * @param stream a stream object
-     * @param ${rootLcapName} a ${root.name} object
-     * @throws java.io.IOException java.io.IOException if any.
-     */
-    public void write( OutputStream stream, ${root.name} ${rootLcapName} )
-        throws java.io.IOException
-    {
-        XmlSerializer serializer = new MXSerializer();
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-indentation", "  " );
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-line-separator", "\n" );
-        serializer.setOutput( stream, ${rootLcapName}.getModelEncoding() );
-        serializer.startDocument( ${rootLcapName}.getModelEncoding(), null );
-        write${root.name}( "$rootTag", ${rootLcapName}, serializer );
-        serializer.endDocument();
-    } //-- void write( OutputStream, ${root.name} )
-
-    /**
-     * Method writeDomToSerializer.
-     *
-     * @param dom a dom object.
-     * @param serializer a serializer object.
-     * @throws java.io.IOException java.io.IOException if any.
-     */
-    protected void writeDomToSerializer( org.apache.maven.api.xml.XmlNode dom, XmlSerializer serializer )
-        throws java.io.IOException
-    {
-        serializer.startTag( NAMESPACE, dom.getName() );
-
-        for ( Map.Entry<String, String> attribute : dom.getAttributes().entrySet() )
-        {
-            serializer.attribute( NAMESPACE, attribute.getKey(), attribute.getValue() );
-        }
-        for ( XmlNode aChild : dom.getChildren() )
-        {
-            writeDomToSerializer( aChild, serializer );
-        }
-
-        String value = dom.getValue();
-        if ( value != null )
-        {
-            serializer.text( value );
-        }
-
-        serializer.endTag( NAMESPACE, dom.getName() );
-
-    } //-- void writeDomToSerializer( org.apache.maven.api.xml.XmlNode, XmlSerializer )
-
-
-#foreach ( $class in $model.allClasses )
- #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-  #set ( $classUcapName = $Helper.capitalise( $class.name ) )
-  #set ( $classLcapName = $Helper.uncapitalise( $class.name ) )
-  #set ( $allFields = $Helper.xmlFields( $class ) )
-    private void write${classUcapName}( String tagName, ${classUcapName} ${classLcapName}, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( ${classLcapName} != null )
-        {
-  #if ( $class == $root )
-            if ( this.fileComment != null )
-            {
-                serializer.comment(this.fileComment);
-            }
-            serializer.setPrefix( "", "http://maven.apache.org/POM/4.0.0" );
-            serializer.setPrefix( "xsi", "http://www.w3.org/2001/XMLSchema-instance" );
-            serializer.startTag( NAMESPACE, tagName );
-            serializer.attribute( "", "xsi:schemaLocation", "http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" );
-  #else
-            serializer.startTag( NAMESPACE, tagName );
-  #end
-  #foreach ( $field in $allFields )
-    #if ( $Helper.xmlFieldMetadata( $field ).attribute )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-      #if ( $field.type == "String" )
-            writeAttr( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #else
-        // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    #end
-  #end
-  #foreach ( $field in $allFields )
-    #if ( ! $Helper.xmlFieldMetadata( $field ).attribute && ! $Helper.xmlFieldMetadata( $field ).transient )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #if ( ! $fieldTagName )
-        #set ( $fieldTagName = $field.name )
-      #end
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-      #set ( $def = ${field.defaultValue} )
-      #if ( $field.type == "String" )
-        #if ( ! $def )
-            writeTag( "$fieldTagName", null, ${classLcapName}.get${fieldCapName}(), serializer );
-        #else
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.get${fieldCapName}(), serializer );
-        #end
-      #elseif ( $field.type == "boolean" || $field.type == "Boolean" )
-        #if ( ${def} == "true" )
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.is${fieldCapName}() ? null : "false", serializer );
-        #else
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.is${fieldCapName}() ? "true" : null, serializer );
-        #end
-      #elseif ( $field.type == "int" )
-            writeTag( "$fieldTagName", "${def}", Integer.toString( ${classLcapName}.get${fieldCapName}() ), serializer );
-      #elseif ( $field.type == "DOM" )
-            writeDom( ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-        #set( $singularField = ${Helper.singular($fieldTagName)} )
-            writeList( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer, t -> writeTag( "$singularField", "${def}", t, serializer ) );
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-            writeProperties( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.to && $field.multiplicity == "1" )
-            write${field.to}( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.to && $field.multiplicity == "*" )
-        #set( $singularField = ${Helper.singular($fieldTagName)} )
-            writeList( "$fieldTagName", $Helper.isFlatItems($field), ${classLcapName}.get${fieldCapName}(), serializer, t -> write${field.to}( "$singularField", t, serializer ) );
-      #else
-            // TODO: name=${field.name} type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    #end
-  #end
-            serializer.endTag( NAMESPACE, tagName );
-        }
-    }
-
- #end
-#end
-    @FunctionalInterface
-    private interface ElementWriter<T>
-    {
-        public void write( T t ) throws IOException;
-    }
-
-    private <T> void writeList( String tagName, List<T> list, XmlSerializer serializer, ElementWriter<T> writer )
-        throws IOException
-    {
-        writeList( tagName, false, list, serializer, writer );
-    }
-
-    private <T> void writeList( String tagName, boolean flat, List<T> list, XmlSerializer serializer, ElementWriter<T> writer )
-        throws IOException
-    {
-        if ( list != null && !list.isEmpty() )
-        {
-            if ( !flat )
-            {
-                serializer.startTag( NAMESPACE, tagName );
-            }
-            for ( T t : list )
-            {
-                writer.write( t );
-            }
-            if ( !flat )
-            {
-                serializer.endTag( NAMESPACE, tagName );
-            }
-        }
-    }
-
-    private <T> void writeProperties( String tagName, Properties props, XmlSerializer serializer )
-            throws IOException
-    {
-        if ( props != null && !props.isEmpty() )
-        {
-            serializer.startTag( NAMESPACE, tagName );
-            for ( Map.Entry<Object, Object> entry : props.entrySet() )
-            {
-                writeTag( entry.getKey().toString(), null, entry.getValue().toString(), serializer );
-            }
-            serializer.endTag( NAMESPACE, tagName );
-        }
-    }
-
-    private void writeDom( XmlNode dom, XmlSerializer serializer )
-            throws IOException
-    {
-        if ( dom != null )
-        {
-            serializer.startTag( NAMESPACE, dom.getName() );
-            for ( Map.Entry<String, String> attr : dom.getAttributes().entrySet() )
-            {
-                serializer.attribute( NAMESPACE, attr.getKey(), attr.getValue() );
-            }
-            for ( XmlNode child : dom.getChildren() )
-            {
-                writeDom( child, serializer );
-            }
-            String value = dom.getValue();
-            if ( value != null )
-            {
-                serializer.text( value );
-            }
-            serializer.endTag( NAMESPACE, dom.getName() );
-        }
-    }
-
-    private void writeTag( String tagName, String defaultValue, String value, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( value != null && !Objects.equals( defaultValue, value ) )
-        {
-            serializer.startTag( NAMESPACE, tagName ).text( value ).endTag( NAMESPACE, tagName );
-        }
-    }
-
-    private void writeAttr( String attrName, String value, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( value != null )
-        {
-            serializer.attribute( NAMESPACE, attrName, value );
-        }
-    }
-
-}
diff --git a/maven-settings/pom.xml b/maven-settings/pom.xml
index ee70516934cc..be088709b62d 100644
--- a/maven-settings/pom.xml
+++ b/maven-settings/pom.xml
@@ -50,38 +50,15 @@ under the License.
 
   <build>
     <plugins>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-dependency-plugin</artifactId>
-        <executions>
-          <execution>
-            <id>copy-settings.mdo</id>
-            <goals>
-              <goal>copy</goal>
-            </goals>
-            <phase>generate-sources</phase>
-            <configuration>
-              <artifactItems>
-                <artifactItem>
-                  <groupId>org.apache.maven</groupId>
-                  <artifactId>maven-api-settings</artifactId>
-                  <version>${project.version}</version>
-                  <type>mdo</type>
-                  <outputDirectory>target/mdo/</outputDirectory>
-                  <destFileName>settings.mdo</destFileName>
-                </artifactItem>
-              </artifactItems>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
       <plugin>
         <groupId>org.codehaus.modello</groupId>
         <artifactId>modello-maven-plugin</artifactId>
         <configuration>
           <version>2.0.0</version>
+          <basedir>${project.basedir}/../api/maven-api-settings</basedir>
+          <velocityBasedir>${project.basedir}/../src/mdo</velocityBasedir>
           <models>
-            <model>target/mdo/settings.mdo</model>
+            <model>src/main/mdo/settings.mdo</model>
           </models>
         </configuration>
         <executions>
@@ -93,10 +70,10 @@ under the License.
             <phase>generate-sources</phase>
             <configuration>
               <templates>
-                <template>src/main/mdo/model-v3.vm</template>
-                <template>src/main/mdo/merger.vm</template>
-                <template>src/main/mdo/reader.vm</template>
-                <template>src/main/mdo/writer.vm</template>
+                <template>model-v3.vm</template>
+                <template>merger.vm</template>
+                <template>reader.vm</template>
+                <template>writer.vm</template>
               </templates>
               <params>
                 <param>packageModelV3=org.apache.maven.settings</param>
diff --git a/maven-settings/src/main/mdo/common.vm b/maven-settings/src/main/mdo/common.vm
deleted file mode 100644
index aa3d17a0398e..000000000000
--- a/maven-settings/src/main/mdo/common.vm
+++ /dev/null
@@ -1,21 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-##
-## Nothing special to do here
-##
\ No newline at end of file
diff --git a/maven-settings/src/main/mdo/writer.vm b/maven-settings/src/main/mdo/writer.vm
deleted file mode 100644
index 7b2c805d3607..000000000000
--- a/maven-settings/src/main/mdo/writer.vm
+++ /dev/null
@@ -1,331 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Xpp3Writer" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#set ( $rootXml = $Helper.xmlClassMetadata( $root ) )
-#set ( $rootTag = $rootXml.tagName )
-#set ( $rootUcapName = $Helper.capitalise( $root.name ) )
-#set ( $rootLcapName = $Helper.uncapitalise( $root.name ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.io.Reader;
-import java.io.Writer;
-import java.text.DateFormat;
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Properties;
-import java.util.Set;
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.api.xml.XmlNode;
-import org.apache.maven.internal.xml.XmlNodeBuilder;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.name};
-#end
-import org.codehaus.plexus.util.ReaderFactory;
-import org.codehaus.plexus.util.xml.pull.EntityReplacementMap;
-import org.codehaus.plexus.util.xml.pull.MXParser;
-import org.codehaus.plexus.util.xml.pull.MXSerializer;
-import org.codehaus.plexus.util.xml.pull.XmlPullParser;
-import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
-import org.codehaus.plexus.util.xml.pull.XmlSerializer;
-
-@Generated
-public class ${className}
-{
-      //--------------------------/
-     //- Class/Member Variables -/
-    //--------------------------/
-
-    /**
-     * Field NAMESPACE.
-     */
-    private static final String NAMESPACE = null;
-
-    /**
-     * Field fileComment.
-     */
-    private String fileComment = null;
-
-
-      //-----------/
-     //- Methods -/
-    //-----------/
-
-    /**
-     * Method setFileComment.
-     *
-     * @param fileComment a fileComment object.
-     */
-    public void setFileComment( String fileComment )
-    {
-        this.fileComment = fileComment;
-    } //-- void setFileComment( String )
-
-    /**
-     * Method write.
-     *
-     * @param writer a writer object
-     * @param ${rootLcapName} a ${root.name} object
-     * @throws java.io.IOException java.io.IOException if any
-     */
-    public void write( Writer writer, ${root.name} ${rootLcapName} )
-        throws java.io.IOException
-    {
-        XmlSerializer serializer = new MXSerializer();
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-indentation", "  " );
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-line-separator", "\n" );
-        serializer.setOutput( writer );
-        serializer.startDocument( ${rootLcapName}.getModelEncoding(), null );
-        write${root.name}( "$rootTag", ${rootLcapName}, serializer );
-        serializer.endDocument();
-    } //-- void write( Writer, ${root.name} )
-
-    /**
-     * Method write.
-     *
-     * @param stream a stream object
-     * @param ${rootLcapName} a ${root.name} object
-     * @throws java.io.IOException java.io.IOException if any
-     */
-    public void write( OutputStream stream, ${root.name} ${rootLcapName} )
-        throws java.io.IOException
-    {
-        XmlSerializer serializer = new MXSerializer();
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-indentation", "  " );
-        serializer.setProperty( "http://xmlpull.org/v1/doc/properties.html#serializer-line-separator", "\n" );
-        serializer.setOutput( stream, ${rootLcapName}.getModelEncoding() );
-        serializer.startDocument( ${rootLcapName}.getModelEncoding(), null );
-        write${root.name}( "$rootTag", ${rootLcapName}, serializer );
-        serializer.endDocument();
-    } //-- void write( OutputStream, ${root.name} )
-
-    /**
-     * Method writeDomToSerializer.
-     *
-     * @param dom a dom object.
-     * @param serializer a serializer object.
-     * @throws java.io.IOException java.io.IOException if any.
-     */
-    protected void writeDomToSerializer( org.apache.maven.api.xml.XmlNode dom, XmlSerializer serializer )
-        throws java.io.IOException
-    {
-        serializer.startTag( NAMESPACE, dom.getName() );
-
-        for ( Map.Entry<String, String> attribute : dom.getAttributes().entrySet() )
-        {
-            serializer.attribute( NAMESPACE, attribute.getKey(), attribute.getValue() );
-        }
-        for ( XmlNode aChild : dom.getChildren() )
-        {
-            writeDomToSerializer( aChild, serializer );
-        }
-
-        String value = dom.getValue();
-        if ( value != null )
-        {
-            serializer.text( value );
-        }
-
-        serializer.endTag( NAMESPACE, dom.getName() );
-
-    } //-- void writeDomToSerializer( org.apache.maven.api.xml.XmlNode, XmlSerializer )
-
-
-#foreach ( $class in $model.allClasses )
- #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-  #set ( $classUcapName = $Helper.capitalise( $class.name ) )
-  #set ( $classLcapName = $Helper.uncapitalise( $class.name ) )
-  #set ( $allFields = $Helper.xmlFields( $class ) )
-    private void write${classUcapName}( String tagName, ${classUcapName} ${classLcapName}, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( ${classLcapName} != null )
-        {
-  #if ( $class == $root )
-            if ( this.fileComment != null )
-            {
-                serializer.comment(this.fileComment);
-            }
-            serializer.setPrefix( "", "http://maven.apache.org/POM/4.0.0" );
-            serializer.setPrefix( "xsi", "http://www.w3.org/2001/XMLSchema-instance" );
-            serializer.startTag( NAMESPACE, tagName );
-            serializer.attribute( "", "xsi:schemaLocation", "http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" );
-  #else
-            serializer.startTag( NAMESPACE, tagName );
-  #end
-  #foreach ( $field in $allFields )
-    #if ( $Helper.xmlFieldMetadata( $field ).attribute )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-      #if ( $field.type == "String" )
-            writeAttr( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #else
-        // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    #end
-  #end
-  #foreach ( $field in $allFields )
-    #if ( ! $Helper.xmlFieldMetadata( $field ).attribute && ! $Helper.xmlFieldMetadata( $field ).transient )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #if ( ! $fieldTagName )
-        #set ( $fieldTagName = $field.name )
-      #end
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-      #set ( $def = ${field.defaultValue} )
-      #if ( $field.type == "String" )
-        #if ( ! $def )
-            writeTag( "$fieldTagName", null, ${classLcapName}.get${fieldCapName}(), serializer );
-        #else
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.get${fieldCapName}(), serializer );
-        #end
-      #elseif ( $field.type == "boolean" || $field.type == "Boolean" )
-        #if ( ${def} == "true" )
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.is${fieldCapName}() ? null : "false", serializer );
-        #else
-            writeTag( "$fieldTagName", "${def}", ${classLcapName}.is${fieldCapName}() ? "true" : null, serializer );
-        #end
-      #elseif ( $field.type == "int" )
-            writeTag( "$fieldTagName", "${def}", Integer.toString( ${classLcapName}.get${fieldCapName}() ), serializer );
-      #elseif ( $field.type == "DOM" )
-            writeDom( ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-        #set( $singularField = ${Helper.singular($fieldTagName)} )
-            writeList( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer, t -> writeTag( "$singularField", "${def}", t, serializer ) );
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-            writeProperties( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.to && $field.multiplicity == "1" )
-            write${field.to}( "$fieldTagName", ${classLcapName}.get${fieldCapName}(), serializer );
-      #elseif ( $field.to && $field.multiplicity == "*" )
-        #set( $singularField = ${Helper.singular($fieldTagName)} )
-            writeList( "$fieldTagName", $Helper.isFlatItems($field), ${classLcapName}.get${fieldCapName}(), serializer, t -> write${field.to}( "$singularField", t, serializer ) );
-      #else
-            // TODO: name=${field.name} type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    #end
-  #end
-            serializer.endTag( NAMESPACE, tagName );
-        }
-    }
-
- #end
-#end
-    @FunctionalInterface
-    private interface ElementWriter<T>
-    {
-        public void write( T t ) throws IOException;
-    }
-
-    private <T> void writeList( String tagName, List<T> list, XmlSerializer serializer, ElementWriter<T> writer )
-        throws IOException
-    {
-        writeList( tagName, false, list, serializer, writer );
-    }
-
-    private <T> void writeList( String tagName, boolean flat, List<T> list, XmlSerializer serializer, ElementWriter<T> writer )
-        throws IOException
-    {
-        if ( list != null && !list.isEmpty() )
-        {
-            if ( !flat )
-            {
-                serializer.startTag( NAMESPACE, tagName );
-            }
-            for ( T t : list )
-            {
-                writer.write( t );
-            }
-            if ( !flat )
-            {
-                serializer.endTag( NAMESPACE, tagName );
-            }
-        }
-    }
-
-    private <T> void writeProperties( String tagName, Map<String, String> props, XmlSerializer serializer )
-            throws IOException
-    {
-        if ( props != null && !props.isEmpty() )
-        {
-            serializer.startTag( NAMESPACE, tagName );
-            for ( Map.Entry<String, String> entry : props.entrySet() )
-            {
-                writeTag( entry.getKey(), null, entry.getValue(), serializer );
-            }
-            serializer.endTag( NAMESPACE, tagName );
-        }
-    }
-
-    private void writeDom( XmlNode dom, XmlSerializer serializer )
-            throws IOException
-    {
-        if ( dom != null )
-        {
-            serializer.startTag( NAMESPACE, dom.getName() );
-            for ( Map.Entry<String, String> attr : dom.getAttributes().entrySet() )
-            {
-                serializer.attribute( NAMESPACE, attr.getKey(), attr.getValue() );
-            }
-            for ( XmlNode child : dom.getChildren() )
-            {
-                writeDom( child, serializer );
-            }
-            String value = dom.getValue();
-            if ( value != null )
-            {
-                serializer.text( value );
-            }
-            serializer.endTag( NAMESPACE, dom.getName() );
-        }
-    }
-
-    private void writeTag( String tagName, String defaultValue, String value, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( value != null && !Objects.equals( defaultValue, value ) )
-        {
-            serializer.startTag( NAMESPACE, tagName ).text( value ).endTag( NAMESPACE, tagName );
-        }
-    }
-
-    private void writeAttr( String attrName, String value, XmlSerializer serializer )
-        throws IOException
-    {
-        if ( value != null )
-        {
-            serializer.attribute( NAMESPACE, attrName, value );
-        }
-    }
-
-}
diff --git a/maven-toolchain-model/pom.xml b/maven-toolchain-model/pom.xml
index 01ecb03cb058..ce241dbac015 100644
--- a/maven-toolchain-model/pom.xml
+++ b/maven-toolchain-model/pom.xml
@@ -49,38 +49,15 @@ under the License.
 
   <build>
     <plugins>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-dependency-plugin</artifactId>
-        <executions>
-          <execution>
-            <id>copy-toolchains.mdo</id>
-            <goals>
-              <goal>copy</goal>
-            </goals>
-            <phase>generate-sources</phase>
-            <configuration>
-              <artifactItems>
-                <artifactItem>
-                  <groupId>org.apache.maven</groupId>
-                  <artifactId>maven-api-toolchain</artifactId>
-                  <version>${project.version}</version>
-                  <type>mdo</type>
-                  <outputDirectory>target/mdo/</outputDirectory>
-                  <destFileName>toolchains.mdo</destFileName>
-                </artifactItem>
-              </artifactItems>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
       <plugin>
         <groupId>org.codehaus.modello</groupId>
         <artifactId>modello-maven-plugin</artifactId>
         <configuration>
           <version>1.1.0</version>
+          <basedir>${project.basedir}/../api/maven-api-toolchain</basedir>
+          <velocityBasedir>${project.basedir}/../src/mdo</velocityBasedir>
           <models>
-            <model>target/mdo/toolchains.mdo</model>
+            <model>src/main/mdo/toolchains.mdo</model>
           </models>
         </configuration>
         <executions>
@@ -92,10 +69,10 @@ under the License.
             <phase>generate-sources</phase>
             <configuration>
               <templates>
-                <template>src/main/mdo/model-v3.vm</template>
-                <template>src/main/mdo/merger.vm</template>
-                <template>src/main/mdo/reader.vm</template>
-                <template>src/main/mdo/writer.vm</template>
+                <template>model-v3.vm</template>
+                <template>merger.vm</template>
+                <template>reader.vm</template>
+                <template>writer.vm</template>
               </templates>
               <params>
                 <param>packageModelV3=org.apache.maven.toolchain.model</param>
diff --git a/maven-toolchain-model/src/main/mdo/common.vm b/maven-toolchain-model/src/main/mdo/common.vm
deleted file mode 100644
index aa3d17a0398e..000000000000
--- a/maven-toolchain-model/src/main/mdo/common.vm
+++ /dev/null
@@ -1,21 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-##
-## Nothing special to do here
-##
\ No newline at end of file
diff --git a/maven-toolchain-model/src/main/mdo/merger.vm b/maven-toolchain-model/src/main/mdo/merger.vm
deleted file mode 100644
index 57d4fab0c928..000000000000
--- a/maven-toolchain-model/src/main/mdo/merger.vm
+++ /dev/null
@@ -1,379 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Merger" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.ObjectStreamException;
-import java.util.AbstractList;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.function.BinaryOperator;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.api.xml.XmlNode;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.Name};
-#end
-
-@Generated
-public class ${className}
-{
-
-    /**
-     * Merges the specified source object into the given target object.
-     *
-     * @param target The target object whose existing contents should be merged with the source, must not be
-     *            <code>null</code>.
-     * @param source The (read-only) source object that should be merged into the target object, may be
-     *            <code>null</code>.
-     * @param sourceDominant A flag indicating whether either the target object or the source object provides the
-     *            dominant data.
-     * @param hints A set of key-value pairs that customized merger implementations can use to carry domain-specific
-     *            information along, may be <code>null</code>.
-     */
-    public ${root.name} merge( ${root.name} target, ${root.name} source, boolean sourceDominant, Map<?, ?> hints )
-    {
-        Objects.requireNonNull( target, "target cannot be null" );
-        if ( source == null )
-        {
-            return target;
-        }
-        Map<Object, Object> context = new HashMap<>();
-        if ( hints != null )
-        {
-            context.putAll( hints );
-        }
-        return merge${root.name}( target, source, sourceDominant, context );
-    }
-
-#foreach ( $class in $model.allClasses )
-  #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-    #set ( $ancestors = $Helper.ancestors( $class ) )
-    #set ( $allFields = [] )
-    #foreach ( $cl in $ancestors )
-      #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-    #end
-    protected ${class.name} merge${class.name}( ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-        ${class.name}.Builder builder = ${class.name}.newBuilder( target );
-        merge${class.name}( builder, target, source, sourceDominant, context );
-        return builder.build();
-    }
-
-    protected void merge${class.name}( ${class.name}.Builder builder, ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-    #if ( $class.superClass )
-        merge${class.superClass}( builder, target ,source, sourceDominant, context );
-    #end
-    #foreach ( $field in $class.getFields($version) )
-        merge${field.modelClass.name}_${Helper.capitalise($field.name)}( builder, target, source, sourceDominant, context );
-    #end
-    }
-
-    #foreach ( $field in $allFields )
-      #set ( $capField = ${Helper.capitalise($field.name)} )
-    protected void merge${class.name}_${capField}( ${class.name}.Builder builder, ${class.name} target, ${class.name} source, boolean sourceDominant, Map<Object, Object> context )
-    {
-      #if ( $field.type == "String" )
-        String src = source.get${capField}();
-        String tgt = target.get${capField}();
-        if ( src != null && ( sourceDominant || tgt == null ) )
-        {
-            builder.${field.name}( src );
-        #if ( $locationTracking )
-            builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-        }
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-        builder.${field.name}( merge( target.get${capField}(), source.get${capField}(), sourceDominant, e -> e ) );
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-        Map<String, String> src = source.get${capField}();
-        if ( !src.isEmpty() )
-        {
-            Map<String, String> tgt = target.get${capField}();
-            if ( tgt.isEmpty() )
-            {
-                builder.${field.name}( src );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-            }
-            else
-            {
-                Map<String, String> merged = new HashMap<>();
-                merged.putAll( sourceDominant ? target.get${capField}() : source.get${capField}() );
-                merged.putAll( sourceDominant ? source.get${capField}() : target.get${capField}() );
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", InputLocation.merge( target.getLocation( "${field.name}" ), source.getLocation( "${field.name}" ), sourceDominant ) );
-        #end
-            }
-        }
-      #elseif ( $field.to && $field.multiplicity == "1" )
-        ${field.to} src = source.get${capField}();
-        if ( src != null )
-        {
-            ${field.to} tgt = target.get${capField}();
-            if ( tgt == null )
-            {
-                tgt = ${field.to}.newInstance( false );
-            }
-            ${field.to} merged = merge${field.to}( tgt, src, sourceDominant, context );
-            if ( merged == src )
-            {
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", source.getLocation( "${field.name}" ) );
-        #end
-            }
-            else if ( merged != tgt )
-            {
-                builder.${field.name}( merged );
-        #if ( $locationTracking )
-                builder.location( "${field.name}", InputLocation.merge( target.getLocation( "${field.name}" ), source.getLocation( "${field.name}" ), sourceDominant ) );
-        #end
-            }
-        }
-      #elseif ( $field.to && $field.multiplicity == "*" )
-        builder.${field.name}( merge( target.get${capField}(), source.get${capField}(), sourceDominant, get${field.to}Key() ) );
-      #elseif ( $field.type == "DOM" )
-        XmlNode src = source.getConfiguration();
-        if ( src != null )
-        {
-            XmlNode tgt = target.getConfiguration();
-            if ( tgt == null )
-            {
-                builder.configuration( src );
-            }
-            else if ( sourceDominant )
-            {
-                builder.configuration( src.merge( tgt ) );
-            }
-            else
-            {
-                builder.configuration( tgt.merge( src ) );
-            }
-        }
-      #elseif ( $field.type == "boolean" )
-        if ( sourceDominant )
-        {
-            builder.${field.name}( source.is${capField}() );
-        }
-      #elseif ( $field.type == "int" || $field.type == "java.nio.file.Path" )
-        if ( sourceDominant )
-        {
-            builder.${field.name}( source.get${capField}() );
-        }
-      #else
-        // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-    }
-    #end
-
-  #end
-#end
-
-#foreach ( $class in $model.allClasses )
-  #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-    protected KeyComputer<${class.name}> get${class.name}Key()
-    {
-        return v -> v;
-    }
-  #end
-#end
-
-    /**
-     * Use to compute keys for data structures
-     * @param <T> the data structure type
-     */
-    @FunctionalInterface
-    public interface KeyComputer<T> extends Function<T, Object>
-    {
-    }
-
-    /**
-     * Merge two lists
-     */
-    public static <T> List<T> merge( List<T> tgt, List<T> src, boolean sourceDominant, KeyComputer<T> computer )
-    {
-        return merge( tgt, src, computer, ( t, s ) -> sourceDominant ? s : t );
-    }
-
-    public static <T> List<T> merge( List<T> tgt, List<T> src, KeyComputer<T> computer, BinaryOperator<T> remapping )
-    {
-        if ( src.isEmpty() )
-        {
-            return tgt;
-        }
-
-        MergingList<T> list;
-        if ( tgt instanceof MergingList )
-        {
-            list = (MergingList<T>) tgt;
-        }
-        else
-        {
-            list = new MergingList<>( computer, src.size() + tgt.size() );
-            list.mergeAll( tgt, ( t, s ) -> s );
-        }
-
-        list.mergeAll( src, remapping );
-        return list;
-    }
-
-    /**
-     * Merging list
-     * @param <V>
-     */
-    private static class MergingList<V> extends AbstractList<V> implements java.io.Serializable
-    {
-
-        private final KeyComputer<V> keyComputer;
-        private Map<Object, V> map;
-        private List<V> list;
-
-        MergingList( KeyComputer<V> keyComputer, int initialCapacity )
-        {
-            this.map = new LinkedHashMap<>( initialCapacity );
-            this.keyComputer = keyComputer;
-        }
-
-        Object writeReplace() throws ObjectStreamException
-        {
-            return new ArrayList<>( this );
-        }
-
-        @Override
-        public Iterator<V> iterator()
-        {
-            if ( map != null )
-            {
-                return map.values().iterator();
-            }
-            else
-            {
-                return list.iterator();
-            }
-        }
-
-        void mergeAll( Collection<V> vs, BinaryOperator<V> remapping )
-        {
-            if ( map == null )
-            {
-                map = list.stream().collect( Collectors.toMap( keyComputer,
-                                                               Function.identity(),
-                                                               null,
-                                                               LinkedHashMap::new ) );
-
-                list = null;
-            }
-
-            if ( vs instanceof MergingList && ( (MergingList<V>) vs ).map != null )
-            {
-                for ( Map.Entry<Object, V> e : ( (MergingList<V>) vs ).map.entrySet() )
-                {
-                    Object key = e.getKey();
-                    V v = e.getValue();
-                    map.merge( key, v, remapping );
-                }
-            }
-            else
-            {
-                for ( V v : vs )
-                {
-                    Object key = keyComputer.apply( v );
-
-                    map.merge( key, v, remapping );
-                }
-            }
-        }
-
-        @Override
-        public boolean contains( Object o )
-        {
-            if ( map != null )
-            {
-                return map.containsValue( o );
-            }
-            else
-            {
-                return list.contains( o );
-            }
-        }
-
-        private List<V> asList()
-        {
-            if ( list == null )
-            {
-                list = new ArrayList<>( map.values() );
-                map = null;
-            }
-            return list;
-        }
-
-        @Override
-        public void add( int index, V element )
-        {
-            asList().add( index, element );
-        }
-
-        @Override
-        public V remove( int index )
-        {
-            return asList().remove( index );
-        }
-
-        @Override
-        public V get( int index )
-        {
-            return asList().get( index );
-        }
-
-        @Override
-        public int size()
-        {
-            if ( map != null )
-            {
-                return map.size();
-            }
-            else
-            {
-                return list.size();
-            }
-        }
-    }
-}
diff --git a/maven-toolchain-model/src/main/mdo/model-v3.vm b/maven-toolchain-model/src/main/mdo/model-v3.vm
deleted file mode 100644
index 9e06cff9ba59..000000000000
--- a/maven-toolchain-model/src/main/mdo/model-v3.vm
+++ /dev/null
@@ -1,255 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageModelV3}" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#
-#foreach ( $class in $model.allClasses )
-  #set ( $ancestors = $Helper.ancestors( $class ) )
-  #set ( $allFields = [] )
-  #set ( $inheritedFields = [] )
-  #foreach ( $cl in $ancestors )
-    #if ( $cl != $class )
-      #set ( $dummy = $inheritedFields.addAll( $cl.allFields ) )
-    #end
-    #set ( $dummy = $allFields.addAll( $cl.allFields ) )
-  #end
-  #set ( $className = "${class.name}" )
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-  #if ( $class.name != "InputLocation" && $class.name != "InputSource" )
-    #set ( $types = { } )
-    #set ( $imports = $class.getClass().forName("java.util.TreeSet").newInstance() )
-    #set ( $dummy = $imports.add( "java.io.Serializable" ) )
-    #set ( $dummy = $imports.add( "java.util.AbstractList" ) )
-    #set ( $dummy = $imports.add( "java.util.Collections" ) )
-    #set ( $dummy = $imports.add( "java.util.HashMap" ) )
-    #set ( $dummy = $imports.add( "java.util.List" ) )
-    #set ( $dummy = $imports.add( "java.util.Map" ) )
-    #set ( $dummy = $imports.add( "java.util.stream.Collectors" ) )
-    #set ( $dummy = $imports.add( "java.util.stream.Stream" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Generated" ) )
-    #set ( $dummy = $imports.add( "org.apache.maven.api.annotations.Nonnull" ) )
-    #foreach ( $field in $allFields )
-      #if ( $field.type == "java.util.List" )
-          #set ( $dummy = $imports.add( "java.util.ArrayList" ) )
-          #set ( $dummy = $types.put( $field, "List<" + $field.to + ">" ) )
-      #elseif ( $field.type == "DOM" )
-          #set ( $dummy = $imports.add( "org.codehaus.plexus.util.xml.Xpp3Dom" ) )
-          #set ( $dummy = $types.put( $field, "Object" ) )
-      #else
-        #set ( $fieldType = ${types.getOrDefault($field.type,$field.type)} )
-        #set ( $idx = $fieldType.lastIndexOf('.') )
-        #if ( $idx > 0 )
-          #set ( $dummy = $imports.add( $fieldType ) )
-          #set ( $dummy = $types.put( $fieldType, $fieldType.substring( $idx + 1 ) ) )
-        #end
-      #end
-    #end
-    #set ( $eq = "" )
-    #set ( $hc = "" )
-    #foreach ( $field in $allFields )
-      #if ( $field.identifier )
-        #set ( $dummy = $imports.add( "java.util.Objects" ) )
-        #set ( $dummy = $identifiers.add( $field ) )
-        #if ( $eq == "" )
-          #set ( $eq = "Objects.equals( this.${field.name}, that.${field.name} )" )
-        #else
-          #set ( $eq = "$eq && Objects.equals( this.${field.name}, that.${field.name} )" )
-        #end
-        #if ( $hc == "" )
-          #set ( $hc = "${field.name}" )
-        #else
-          #set ( $hc = "$hc, this.${field.name}" )
-        #end
-      #end
-    #end
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-  #foreach ( $imp in $imports )
-import $imp;
-  #end
-
-@Generated
-public class ${class.name}
-    #if ( $class.superClass )
-    extends ${class.superClass}
-    #end
-    implements Serializable, Cloneable
-{
-
-    #if ( ! $class.superClass )
-    ${packageModelV4}.${class.name} delegate;
-    #end
-
-    public ${class.name}()
-    {
-        this( ${packageModelV4}.${class.name}.newInstance() );
-    }
-
-    public ${class.name}( ${packageModelV4}.${class.name} delegate )
-    {
-    #if ( $class.superClass )
-        super( delegate );
-    #else
-        this.delegate = delegate;
-    #end
-    }
-
-    public ${class.name} clone()
-    {
-        return new ${class.name}( getDelegate() );
-    }
-
-    #if ( $class.superClass )
-    @Override
-    #end
-    public ${packageModelV4}.${class.name} getDelegate()
-    {
-    #if ( $class.superClass )
-        return ( ${packageModelV4}.${class.name} ) delegate;
-    #else
-        return delegate;
-    #end
-    }
-
-    #if ( ! $eq.empty )
-    @Override
-    public boolean equals( Object o )
-    {
-        if ( this == o )
-        {
-            return true;
-        }
-        if ( o == null || !( o instanceof ${class.name} ) )
-        {
-            return false;
-        }
-        ${class.name} that = ( ${class.name} ) o;
-        return Objects.equals( this.delegate, that.delegate );
-    }
-
-    @Override
-    public int hashCode()
-    {
-        return getDelegate().hashCode();
-    }
-
-    #end
-    #if ( $class == $root )
-    public String getModelEncoding()
-    {
-        return getDelegate().getModelEncoding();
-    }
-
-    #end
-    #foreach ( $field in $class.getFields($version) )
-      #set ( $cap = $Helper.capitalise( $field.name ) )
-      #set ( $type = ${types.getOrDefault($field,${types.getOrDefault($field.type,$field.type)})} )
-      #if ( $type == "boolean" || $type == "Boolean" )
-        #set ( $pfx = "is" )
-      #else
-        #set ( $pfx = "get" )
-      #end
-      #if ( $field.type == "java.util.List" || $field.type == "java.util.Properties" )
-    @Nonnull
-      #end
-    public ${type} ${pfx}${cap}()
-    {
-      #if ( $field.to != "String" && $field.type == "java.util.List" && $field.multiplicity == "*" )
-        return new WrapperList<${field.to}, ${packageModelV4}.${field.to}>(
-                    getDelegate()::get${cap}, l -> delegate = getDelegate().with${cap}( l ),
-                    ${field.to}::new, ${field.to}::getDelegate );
-      #elseif ( $field.to == "String" && $field.type == "java.util.Properties" && $field.multiplicity == "*" )
-        return new WrapperProperties( getDelegate()::get${cap}, this::set${cap} );
-      #elseif ( $field.to == "String" && $field.type == "java.util.List" && $field.multiplicity == "*" )
-        return new WrapperList<String, ${field.to}>( getDelegate()::get${cap}, this::set${cap}, s -> s, s -> s );
-      #elseif ( $field.to )
-        return getDelegate().${pfx}${cap}() != null ? new ${field.to}( getDelegate().${pfx}${cap}() ) : null;
-      #elseif ( $field.type == "DOM" )
-        return getDelegate().${pfx}${cap}() != null ? new Xpp3Dom( getDelegate().${pfx}${cap}() ) : null;
-      #else
-        return getDelegate().${pfx}${cap}();
-      #end
-    }
-
-    public void set${cap}( ${type} ${field.name} )
-    {
-      #if ( $field.type == "DOM" )
-        delegate = getDelegate().with${cap}( ( ( Xpp3Dom ) ${field.name} ).getDom() );
-      #elseif( $field.type == "java.util.Properties" )
-        Map<String, String> map = ${field.name}.entrySet().stream()
-                .collect( Collectors.toMap( e -> e.getKey().toString(), e -> e.getValue().toString() ) );
-        delegate = getDelegate().with${cap}( map );
-      #elseif ( $field.to != "String" && $field.type == "java.util.List" && $field.multiplicity == "*" )
-        delegate = getDelegate().with${cap}(
-                ${field.name}.stream().map( c -> c.getDelegate() ).collect( Collectors.toList() ) );
-      #elseif ( $field.to && $field.to != "String" )
-        delegate = getDelegate().with${cap}( ${field.name}.getDelegate() );
-      #else
-        delegate = getDelegate().with${cap}( ${field.name} );
-      #end
-    }
-
-      #if ( $field.type == "java.util.List" && $field.multiplicity == "*" )
-        #set ( $v = $Helper.singular( ${field.name} ) )
-        #set ( $scap = $Helper.capitalise( $v ) )
-    public void add${scap}( ${field.to} ${v} )
-    {
-        #if ( $field.to == "String" )
-        delegate = getDelegate().with${cap}(
-                Stream.concat( getDelegate().get${cap}().stream(), Stream.of( ${v} ) )
-                        .collect( Collectors.toList() ) );
-        #else
-        delegate = getDelegate().with${cap}(
-                Stream.concat( getDelegate().get${cap}().stream(), Stream.of( ${v}.getDelegate() ) )
-                        .collect( Collectors.toList() ) );
-        #end
-    }
-
-      #elseif ( $field.type == "java.util.Properties" && $field.multiplicity == "*" )
-        #set ( $v = $Helper.singular( ${field.name} ) )
-        #set ( $scap = $Helper.capitalise( $v ) )
-    public void add${scap}( String key, String value )
-    {
-        get${cap}().put( key, value );
-    }
-
-      #end
-    #end
-    public static List<${packageModelV4}.${class.name}> ${Helper.uncapitalise(${class.name})}ToApiV4( List<${class.name}> list )
-    {
-        return list != null ? new WrapperList<>( list, ${class.name}::getDelegate, ${class.name}::new ) : null;
-    }
-
-    public static List<${class.name}> ${Helper.uncapitalise(${class.name})}ToApiV3( List<${packageModelV4}.${class.name}> list )
-    {
-        return list != null ? new WrapperList<>( list, ${class.name}::new, ${class.name}::getDelegate ) : null;
-    }
-
-    #foreach ( $cs in $class.getCodeSegments($version) )
-$cs.code
-    #end
-}
-  #end
-#end
diff --git a/maven-toolchain-model/src/main/mdo/reader.vm b/maven-toolchain-model/src/main/mdo/reader.vm
deleted file mode 100644
index 02e9199ba8c1..000000000000
--- a/maven-toolchain-model/src/main/mdo/reader.vm
+++ /dev/null
@@ -1,902 +0,0 @@
-#*
-  Licensed to the Apache Software Foundation (ASF) under one
-  or more contributor license agreements.  See the NOTICE file
-  distributed with this work for additional information
-  regarding copyright ownership.  The ASF licenses this file
-  to you under the Apache License, Version 2.0 (the
-  "License"); you may not use this file except in compliance
-  with the License.  You may obtain a copy of the License at
-
-  http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing,
-  software distributed under the License is distributed on an
-  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-  KIND, either express or implied.  See the License for the
-  specific language governing permissions and limitations
-  under the License.
-*#
-#parse ( "src/main/mdo/common.vm" )
-#
-#set ( $package = "${packageToolV4}" )
-#set ( $className = "${model.name}Xpp3Reader" )
-#
-#set ( $root = $model.getClass( $model.getRoot($version), $version ) )
-#set ( $rootXml = $Helper.xmlClassMetadata( $root ) )
-#set ( $rootTag = $rootXml.tagName )
-#set ( $rootUcapName = $Helper.capitalise( $root.name ) )
-#set ( $rootLcapName = $Helper.uncapitalise( $root.name ) )
-#
-#MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
-// =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
-// ==============================================================
-package ${package};
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.Reader;
-import java.text.DateFormat;
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Properties;
-import java.util.Set;
-import org.apache.maven.api.annotations.Generated;
-import org.apache.maven.internal.xml.XmlNodeBuilder;
-#foreach ( $class in $model.allClasses )
-import ${packageModelV4}.${class.name};
-#end
-import org.codehaus.plexus.util.ReaderFactory;
-import org.codehaus.plexus.util.xml.pull.EntityReplacementMap;
-import org.codehaus.plexus.util.xml.pull.MXParser;
-import org.codehaus.plexus.util.xml.pull.XmlPullParser;
-import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
-
-@Generated
-public class ${className}
-{
-    private boolean addDefaultEntities = true;
-
-    private final ContentTransformer contentTransformer;
-
-    public ${className}()
-    {
-        this( ( s, f ) -> s );
-    }
-
-    public ${className}( ContentTransformer contentTransformer )
-    {
-        this.contentTransformer = contentTransformer;
-    }
-
-    /**
-     * Method checkFieldWithDuplicate.
-     *
-     * @param parser a parser object.
-     * @param parsed a parsed object.
-     * @param alias a alias object.
-     * @param tagName a tagName object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return boolean
-     */
-    private boolean checkFieldWithDuplicate( XmlPullParser parser, String tagName, String alias, Set<String> parsed )
-        throws XmlPullParserException
-    {
-        if ( !( parser.getName().equals( tagName ) || parser.getName().equals( alias ) ) )
-        {
-            return false;
-        }
-        if ( !parsed.add( tagName ) )
-        {
-            throw new XmlPullParserException( "Duplicated tag: '" + tagName + "'", parser, null );
-        }
-        return true;
-    } //-- boolean checkFieldWithDuplicate( XmlPullParser, String, String, Set<String> )
-
-    /**
-     * Method checkUnknownAttribute.
-     *
-     * @param parser a parser object.
-     * @param strict a strict object.
-     * @param tagName a tagName object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @throws IOException IOException if any.
-     */
-    private void checkUnknownAttribute( XmlPullParser parser, String attribute, String tagName, boolean strict )
-        throws XmlPullParserException, IOException
-    {
-        // strictXmlAttributes = true for model: if strict == true, not only elements are checked but attributes too
-        if ( strict )
-        {
-            throw new XmlPullParserException( "Unknown attribute '" + attribute + "' for tag '" + tagName + "'", parser, null );
-        }
-    } //-- void checkUnknownAttribute( XmlPullParser, String, String, boolean )
-
-    /**
-     * Method checkUnknownElement.
-     *
-     * @param parser a parser object.
-     * @param strict a strict object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @throws IOException IOException if any.
-     */
-    private void checkUnknownElement( XmlPullParser parser, boolean strict )
-        throws XmlPullParserException, IOException
-    {
-        if ( strict )
-        {
-            throw new XmlPullParserException( "Unrecognised tag: '" + parser.getName() + "'", parser, null );
-        }
-
-        for ( int unrecognizedTagCount = 1; unrecognizedTagCount > 0; )
-        {
-            int eventType = parser.next();
-            if ( eventType == XmlPullParser.START_TAG )
-            {
-                unrecognizedTagCount++;
-            }
-            else if ( eventType == XmlPullParser.END_TAG )
-            {
-                unrecognizedTagCount--;
-            }
-        }
-    } //-- void checkUnknownElement( XmlPullParser, boolean )
-
-    /**
-     * Returns the state of the "add default entities" flag.
-     *
-     * @return boolean
-     */
-    public boolean getAddDefaultEntities()
-    {
-        return addDefaultEntities;
-    } //-- boolean getAddDefaultEntities()
-
-    /**
-     * Method getBooleanValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return boolean
-     */
-    private boolean getBooleanValue( String s, String attribute, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        return getBooleanValue( s, attribute, parser, null );
-    } //-- boolean getBooleanValue( String, String, XmlPullParser )
-
-    /**
-     * Method getBooleanValue.
-     *
-     * @param s a s object.
-     * @param defaultValue a defaultValue object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return boolean
-     */
-    private boolean getBooleanValue( String s, String attribute, XmlPullParser parser, String defaultValue )
-        throws XmlPullParserException
-    {
-        if ( s != null && s.length() != 0 )
-        {
-            return Boolean.valueOf( s ).booleanValue();
-        }
-        if ( defaultValue != null )
-        {
-            return Boolean.valueOf( defaultValue ).booleanValue();
-        }
-        return false;
-    } //-- boolean getBooleanValue( String, String, XmlPullParser, String )
-
-    /**
-     * Method getByteValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return byte
-     */
-    private byte getByteValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Byte.valueOf( s ).byteValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a byte", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- byte getByteValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getCharacterValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return char
-     */
-    private char getCharacterValue( String s, String attribute, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            return s.charAt( 0 );
-        }
-        return 0;
-    } //-- char getCharacterValue( String, String, XmlPullParser )
-
-    /**
-     * Method getDateValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return Date
-     */
-    private Date getDateValue( String s, String attribute, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        return getDateValue( s, attribute, null, parser );
-    } //-- Date getDateValue( String, String, XmlPullParser )
-
-    /**
-     * Method getDateValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param dateFormat a dateFormat object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return Date
-     */
-    private Date getDateValue( String s, String attribute, String dateFormat, XmlPullParser parser )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            String effectiveDateFormat = dateFormat;
-            if ( dateFormat == null )
-            {
-                effectiveDateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS";
-            }
-            if ( "long".equals( effectiveDateFormat ) )
-            {
-                try
-                {
-                    return new java.util.Date( Long.parseLong( s ) );
-                }
-                catch ( NumberFormatException e )
-                {
-                    throw new XmlPullParserException( e.getMessage(), parser, e );
-                }
-            }
-            else
-            {
-                try
-                {
-                    DateFormat dateParser = new java.text.SimpleDateFormat( effectiveDateFormat, java.util.Locale.US );
-                    return dateParser.parse( s );
-                }
-                catch ( java.text.ParseException e )
-                {
-                    throw new XmlPullParserException( e.getMessage(), parser, e );
-                }
-            }
-        }
-        return null;
-    } //-- Date getDateValue( String, String, String, XmlPullParser )
-
-    /**
-     * Method getDoubleValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return double
-     */
-    private double getDoubleValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Double.valueOf( s ).doubleValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a floating point number", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- double getDoubleValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getFloatValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return float
-     */
-    private float getFloatValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Float.valueOf( s ).floatValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a floating point number", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- float getFloatValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getIntegerValue.
-     *
-     * @param s a s object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return int
-     */
-    private int getIntegerValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        return getIntegerValue( s, attribute, parser, strict, 0 );
-    } //-- int getBooleanValue( String, String, XmlPullParser )
-
-    /**
-     * Method getIntegerValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return int
-     */
-    private int getIntegerValue( String s, String attribute, XmlPullParser parser, boolean strict, int defaultValue )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Integer.valueOf( s ).intValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be an integer", parser, nfe );
-                }
-            }
-        }
-        return defaultValue;
-    } //-- int getIntegerValue( String, String, XmlPullParser, boolean, int )
-
-    /**
-     * Method getLongValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return long
-     */
-    private long getLongValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Long.valueOf( s ).longValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a long integer", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- long getLongValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getRequiredAttributeValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return String
-     */
-    private String getRequiredAttributeValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s == null )
-        {
-            if ( strict )
-            {
-                throw new XmlPullParserException( "Missing required value for attribute '" + attribute + "'", parser, null );
-            }
-        }
-        return s;
-    } //-- String getRequiredAttributeValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getShortValue.
-     *
-     * @param s a s object.
-     * @param strict a strict object.
-     * @param parser a parser object.
-     * @param attribute a attribute object.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return short
-     */
-    private short getShortValue( String s, String attribute, XmlPullParser parser, boolean strict )
-        throws XmlPullParserException
-    {
-        if ( s != null )
-        {
-            try
-            {
-                return Short.valueOf( s ).shortValue();
-            }
-            catch ( NumberFormatException nfe )
-            {
-                if ( strict )
-                {
-                    throw new XmlPullParserException( "Unable to parse element '" + attribute + "', must be a short integer", parser, nfe );
-                }
-            }
-        }
-        return 0;
-    } //-- short getShortValue( String, String, XmlPullParser, boolean )
-
-    /**
-     * Method getTrimmedValue.
-     *
-     * @param s a s object.
-     * @return String
-     */
-    private String getTrimmedValue( String s )
-    {
-        if ( s != null )
-        {
-            s = s.trim();
-        }
-        return s;
-    } //-- String getTrimmedValue( String )
-
-    /**
-     * Method interpolatedTrimmed.
-     *
-     * @param value a value object.
-     * @param context a context object.
-     * @return String
-     */
-    private String interpolatedTrimmed( String value, String context )
-    {
-        return getTrimmedValue( contentTransformer.transform( value, context ) );
-    } //-- String interpolatedTrimmed( String, String )
-
-    /**
-     * Method nextTag.
-     *
-     * @param parser a parser object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return int
-     */
-    private int nextTag( XmlPullParser parser )
-        throws IOException, XmlPullParserException
-    {
-        int eventType = parser.next();
-        if ( eventType == XmlPullParser.TEXT )
-        {
-            eventType = parser.next();
-        }
-        if ( eventType != XmlPullParser.START_TAG && eventType != XmlPullParser.END_TAG )
-        {
-            throw new XmlPullParserException( "expected START_TAG or END_TAG not " + XmlPullParser.TYPES[eventType], parser, null );
-        }
-        return eventType;
-    } //-- int nextTag( XmlPullParser )
-
-    /**
-     * @see ReaderFactory#newXmlReader
-     *
-     * @param reader a reader object.
-     * @param strict a strict object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( Reader reader, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        XmlPullParser parser = addDefaultEntities ? new MXParser(EntityReplacementMap.defaultEntityReplacementMap) : new MXParser( );
-
-        parser.setInput( reader );
-
-
-        return read( parser, strict );
-    } //-- ${root.name} read( Reader, boolean )
-
-    /**
-     * @see ReaderFactory#newXmlReader
-     *
-     * @param reader a reader object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( Reader reader )
-        throws IOException, XmlPullParserException
-    {
-        return read( reader, true );
-    } //-- ${root.name} read( Reader )
-
-    /**
-     * Method read.
-     *
-     * @param in a in object.
-     * @param strict a strict object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( InputStream in, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        return read( ReaderFactory.newXmlReader( in ), strict );
-    } //-- ${root.name} read( InputStream, boolean )
-
-    /**
-     * Method read.
-     *
-     * @param in a in object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( InputStream in )
-        throws IOException, XmlPullParserException
-    {
-        return read( ReaderFactory.newXmlReader( in ) );
-    } //-- ${root.name} read( InputStream )
-
-    /**
-     * Method read.
-     *
-     * @param parser a parser object.
-     * @param strict a strict object.
-     * @throws IOException IOException if any.
-     * @throws XmlPullParserException XmlPullParserException if
-     * any.
-     * @return ${root.name}
-     */
-    public ${root.name} read( XmlPullParser parser, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        $rootUcapName $rootLcapName = null;
-        int eventType = parser.getEventType();
-        boolean parsed = false;
-        while ( eventType != XmlPullParser.END_DOCUMENT )
-        {
-            if ( eventType == XmlPullParser.START_TAG )
-            {
-                if ( strict && ! "${rootTag}".equals( parser.getName() ) )
-                {
-                    throw new XmlPullParserException( "Expected root element '${rootTag}' but found '" + parser.getName() + "'", parser, null );
-                }
-                else if ( parsed )
-                {
-                    // fallback, already expected a XmlPullParserException due to invalid XML
-                    throw new XmlPullParserException( "Duplicated tag: '${rootTag}'", parser, null );
-                }
-                $rootLcapName = parse${rootUcapName}( parser, strict );
-                parsed = true;
-            }
-            eventType = parser.next();
-        }
-        if ( parsed )
-        {
-            return $rootLcapName;
-        }
-        throw new XmlPullParserException( "Expected root element '${rootTag}' but found no element at all: invalid XML document", parser, null );
-    } //-- ${root.name} read( XmlPullParser, boolean )
-
-#foreach ( $class in $model.allClasses )
- #if ( $class.name != "InputSource" && $class.name != "InputLocation" )
-  #set ( $classUcapName = $Helper.capitalise( $class.name ) )
-  #set ( $classLcapName = $Helper.uncapitalise( $class.name ) )
-  #set ( $ancestors = $Helper.ancestors( $class ) )
-  #set ( $allFields = [] )
-  #foreach ( $cl in $ancestors )
-    #set ( $dummy = $allFields.addAll( $cl.getFields($version) ) )
-  #end
-    private ${classUcapName} parse${classUcapName}( XmlPullParser parser, boolean strict )
-        throws IOException, XmlPullParserException
-    {
-        String tagName = parser.getName();
-        ${classUcapName}.Builder ${classLcapName} = ${classUcapName}.newBuilder( true );
-        for ( int i = parser.getAttributeCount() - 1; i >= 0; i-- )
-        {
-            String name = parser.getAttributeName( i );
-            String value = parser.getAttributeValue( i );
-            if ( name.indexOf( ':' ) >= 0 )
-            {
-                // just ignore attributes with non-default namespace (for example: xmlns:xsi)
-            }
-  #if ( $class == $root )
-            else if ( "xmlns".equals( name ) )
-            {
-                // ignore xmlns attribute in root class, which is a reserved attribute name
-            }
-  #end
-  #foreach ( $field in $allFields )
-    #if ( $Helper.xmlFieldMetadata( $field ).attribute )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-            else if ( "$fieldTagName".equals( name ) )
-            {
-      #if ( $field.type == "String" )
-                ${classLcapName}.${field.name}( interpolatedTrimmed( value, "$fieldTagName" ) );
-      #elseif ( $field.type == "boolean" || $field.type == "Boolean" )
-                ${classLcapName}.${field.name}( getBooleanValue( interpolatedTrimmed( value, "$fieldTagName" ), "$fieldTagName", parser, "${field.defaultValue}" ) );
-      #else
-                // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-      #end
-            }
-    #end
-  #end
-            else
-            {
-                checkUnknownAttribute( parser, name, tagName, strict );
-            }
-        }
-        Set<String> parsed = new HashSet<>();
-  #foreach ( $field in $allFields )
-    #if ( $Helper.isFlatItems( $field ) )
-        List<$field.to> ${field.name} = new ArrayList<>();
-    #end
-  #end
-        while ( ( strict ? parser.nextTag() : nextTag( parser ) ) == XmlPullParser.START_TAG )
-        {
-            String childName = checkDuplicate( parser.getName(), parser, parsed );
-            switch ( childName )
-            {
-  #set( $ift = "if" )
-  #foreach ( $field in $allFields )
-    #if ( ! $Helper.xmlFieldMetadata( $field ).attribute && ! $Helper.xmlFieldMetadata( $field ).transient )
-      #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-      #if ( ! $fieldTagName )
-        #set ( $fieldTagName = $field.name )
-      #end
-      #if ( $Helper.isFlatItems( $field ) )
-        #set ( $fieldTagName = $Helper.singular( $fieldTagName ) )
-      #end
-      #set ( $fieldCapName = $Helper.capitalise( $field.name ) )
-                case "${fieldTagName}":
-                {
-      #if ( $field.type == "String" )
-                    ${classLcapName}.${field.name}( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ) );
-                    break;
-      #elseif ( $field.type == "boolean" || $field.type == "Boolean" )
-                    ${classLcapName}.${field.name}( getBooleanValue( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ), "${fieldTagName}", parser, "${field.defaultValue}" ) );
-                    break;
-      #elseif ( $field.type == "int" )
-                    ${classLcapName}.${field.name}( getIntegerValue( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ), "${fieldTagName}", parser, strict, ${field.defaultValue} ) );
-                    break;
-      #elseif ( $field.type == "DOM" )
-                    ${classLcapName}.${field.name}( XmlNodeBuilder.build( parser, true ) );
-                    break;
-      #elseif ( $field.type == "java.util.List" && $field.to == "String" && $field.multiplicity == "*" )
-                    List<String> ${field.name} = new ArrayList<>();
-                    while ( parser.nextTag() == XmlPullParser.START_TAG )
-                    {
-                        if ( "${Helper.singular($fieldTagName)}".equals( parser.getName() ) )
-                        {
-                            ${field.name}.add( interpolatedTrimmed( parser.nextText(), "${fieldTagName}" ) );
-                        }
-                        else
-                        {
-                            checkUnknownElement( parser, strict );
-                        }
-                    }
-                    ${classLcapName}.${field.name}( ${field.name} );
-                    break;
-      #elseif ( $field.type == "java.util.Properties" && $field.to == "String" && $field.multiplicity == "*" )
-                    Map<String, String> ${field.name} = new LinkedHashMap<>();
-                    while ( parser.nextTag() == XmlPullParser.START_TAG )
-                    {
-                        String key = parser.getName();
-                        String value = parser.nextText().trim();
-                        ${field.name}.put( key, value );
-                    }
-                    ${classLcapName}.${field.name}( ${field.name} );
-                    break;
-      #elseif ( $field.to && $field.multiplicity == "1" )
-                    ${classLcapName}.${field.name}( parse${field.toClass.name}( parser, strict ) );
-                    break;
-      #elseif ( $field.to && $field.multiplicity == "*" && $Helper.isFlatItems( $field ) )
-                    ${field.name}.add( parse${field.toClass.name}( parser, strict ) );
-                    break;
-      #elseif ( $field.to && $field.multiplicity == "*" )
-                    List<$field.to> ${field.name} = new ArrayList<>();
-                    while ( parser.nextTag() == XmlPullParser.START_TAG )
-                    {
-                        if ( "${Helper.singular($fieldTagName)}".equals( parser.getName() ) )
-                        {
-                            ${field.name}.add( parse${field.toClass.name}( parser, strict ) );
-                        }
-                        else
-                        {
-                            checkUnknownElement( parser, strict );
-                        }
-                    }
-                    ${classLcapName}.${field.name}( ${field.name} );
-                    break;
-      #else
-                    // TODO: type=${field.type} to=${field.to} multiplicity=${field.multiplicity}
-                    break;
-      #end
-                }
-      #set( $ift = "else if" )
-    #end
-  #end
-                default:
-                {
-                    checkUnknownElement( parser, strict );
-                    break;
-                }
-            }
-        }
-  #foreach ( $field in $allFields )
-    #if ( $Helper.isFlatItems( $field ) )
-        ${classLcapName}.${field.name}( ${field.name} );
-    #end
-  #end
-  #if ( $class == $root )
-        ${classLcapName}.modelEncoding( parser.getInputEncoding() );
-  #end
-        return ${classLcapName}.build();
-    }
-
- #end
-#end
-
-    private String checkDuplicate( String tagName, XmlPullParser parser, Set<String> parsed )
-        throws XmlPullParserException
-    {
-#set( $aliases = { } )
-#set( $flats = { } )
-#foreach( $class in $model.allClasses )
-  #foreach ( $field in $class.getFields($version) )
-    #set ( $fieldTagName = $Helper.xmlFieldMetadata( $field ).tagName )
-    #if ( ! $fieldTagName )
-      #set ( $fieldTagName = $field.name )
-    #end
-    #if ( $field.alias )
-      #set ( $dummy = $aliases.put( $field.alias, $fieldTagName ) )
-    #end
-    #if ( $Helper.isFlatItems( $field ) )
-      #set ( $fieldTagName = $Helper.singular($fieldTagName) )
-      #set ( $dummy = $flats.put( $fieldTagName, "" ) )
-    #end
-  #end
-#end
-#if ( ! ${aliases.isEmpty()} )
-        switch ( tagName )
-        {
-  #foreach( $entry in $aliases.entrySet() )
-            case "${entry.key}":
-                tagName = "${entry.value}";
-  #end
-        }
-#end
-#if ( ! ${flats.isEmpty()} )
-        switch ( tagName )
-        {
-  #foreach( $entry in $flats.entrySet() )
-            case "${entry.key}":
-  #end
-                break;
-            default:
-                if ( !parsed.add( tagName ) )
-                {
-                    throw new XmlPullParserException( "Duplicated tag: '" + tagName + "'", parser, null );
-                }
-        }
-#end
-        return tagName;
-    }
-
-    /**
-     * Sets the state of the "add default entities" flag.
-     *
-     * @param addDefaultEntities a addDefaultEntities object.
-     */
-    public void setAddDefaultEntities( boolean addDefaultEntities )
-    {
-        this.addDefaultEntities = addDefaultEntities;
-    } //-- void setAddDefaultEntities( boolean )
-
-    public static interface ContentTransformer
-    {
-        /**
-         * Interpolate the value read from the xpp3 document
-         * @param source The source value
-         * @param fieldName A description of the field being interpolated. The implementation may use this to
-         *                           log stuff.
-         * @return The interpolated value.
-         */
-        String transform( String source, String fieldName );
-    }
-
-}
diff --git a/pom.xml b/pom.xml
index 36820f12e30f..e15feb37f91f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -525,7 +525,7 @@ under the License.
         <plugin>
           <groupId>org.codehaus.modello</groupId>
           <artifactId>modello-maven-plugin</artifactId>
-          <version>2.1.0</version>
+          <version>2.1.1</version>
           <executions>
             <execution>
               <id>modello-site-docs</id>
diff --git a/api/maven-api-model/src/main/mdo/common.vm b/src/mdo/common.vm
similarity index 96%
rename from api/maven-api-model/src/main/mdo/common.vm
rename to src/mdo/common.vm
index e300b2289fea..b8ae20968191 100644
--- a/api/maven-api-model/src/main/mdo/common.vm
+++ b/src/mdo/common.vm
@@ -17,6 +17,7 @@
   under the License.
 *#
 #
+#if ( "${isMavenModel}" == "true" )
 ##
 ## The following loop code is required in order to change the type of the
 ## pomFile attribute to a java.nio.file.Path.  Modello does not support this
@@ -28,4 +29,5 @@
   #end
 #end
 #set ( $locationTracking = true )
+#end
 #
\ No newline at end of file
diff --git a/maven-settings/src/main/mdo/merger.vm b/src/mdo/merger.vm
similarity index 99%
rename from maven-settings/src/main/mdo/merger.vm
rename to src/mdo/merger.vm
index 57d4fab0c928..ff4b81c19dc4 100644
--- a/maven-settings/src/main/mdo/merger.vm
+++ b/src/mdo/merger.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageToolV4}" )
 #set ( $className = "${model.name}Merger" )
@@ -25,7 +25,7 @@
 #
 #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-model/src/main/mdo/model-v3.vm b/src/mdo/model-v3-modified.vm
similarity index 99%
rename from maven-model/src/main/mdo/model-v3.vm
rename to src/mdo/model-v3-modified.vm
index c12c5f0e62cf..0bb0f58b70e2 100644
--- a/maven-model/src/main/mdo/model-v3.vm
+++ b/src/mdo/model-v3-modified.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageModelV3}" )
 #
@@ -83,7 +83,7 @@
       #end
     #end
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-settings/src/main/mdo/model-v3.vm b/src/mdo/model-v3.vm
similarity index 98%
rename from maven-settings/src/main/mdo/model-v3.vm
rename to src/mdo/model-v3.vm
index 9e06cff9ba59..5eb69dd3ae35 100644
--- a/maven-settings/src/main/mdo/model-v3.vm
+++ b/src/mdo/model-v3.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageModelV3}" )
 #
@@ -82,7 +82,7 @@
       #end
     #end
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/api/maven-api-toolchain/src/main/mdo/model.vm b/src/mdo/model.vm
similarity index 99%
rename from api/maven-api-toolchain/src/main/mdo/model.vm
rename to src/mdo/model.vm
index 664064531c64..4a8248ee886b 100644
--- a/api/maven-api-toolchain/src/main/mdo/model.vm
+++ b/src/mdo/model.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageModelV4}" )
 #set ( $root = $model.getClass( $model.getRoot($version), $version ) )
@@ -85,7 +85,7 @@
       #end
     #end
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-model/src/main/mdo/reader-ex.vm b/src/mdo/reader-ex.vm
similarity index 99%
rename from maven-model/src/main/mdo/reader-ex.vm
rename to src/mdo/reader-ex.vm
index f084b41471b3..e92829538000 100644
--- a/maven-model/src/main/mdo/reader-ex.vm
+++ b/src/mdo/reader-ex.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageToolV4}" )
 #set ( $className = "${model.name}Xpp3ReaderEx" )
@@ -29,7 +29,7 @@
 #
 #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-model/src/main/mdo/reader.vm b/src/mdo/reader-modified.vm
similarity index 99%
rename from maven-model/src/main/mdo/reader.vm
rename to src/mdo/reader-modified.vm
index 8c47409d4cda..8787b8241bb7 100644
--- a/maven-model/src/main/mdo/reader.vm
+++ b/src/mdo/reader-modified.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageToolV4}" )
 #set ( $className = "${model.name}Xpp3Reader" )
@@ -29,7 +29,7 @@
 #
 #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-settings/src/main/mdo/reader.vm b/src/mdo/reader.vm
similarity index 99%
rename from maven-settings/src/main/mdo/reader.vm
rename to src/mdo/reader.vm
index 02e9199ba8c1..390fec487c45 100644
--- a/maven-settings/src/main/mdo/reader.vm
+++ b/src/mdo/reader.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageToolV4}" )
 #set ( $className = "${model.name}Xpp3Reader" )
@@ -29,7 +29,7 @@
 #
 #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-model/src/main/mdo/transformer.vm b/src/mdo/transformer.vm
similarity index 98%
rename from maven-model/src/main/mdo/transformer.vm
rename to src/mdo/transformer.vm
index 25a7fe5733a8..34bc3f63ba18 100644
--- a/maven-model/src/main/mdo/transformer.vm
+++ b/src/mdo/transformer.vm
@@ -16,14 +16,14 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageToolV4}" )
 #set ( $className = "${model.name}Transformer" )
 #
 #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-model/src/main/mdo/writer-ex.vm b/src/mdo/writer-ex.vm
similarity index 99%
rename from maven-model/src/main/mdo/writer-ex.vm
rename to src/mdo/writer-ex.vm
index 7eb0e38fad76..4698225d7bef 100644
--- a/maven-model/src/main/mdo/writer-ex.vm
+++ b/src/mdo/writer-ex.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageToolV4}" )
 #set ( $className = "${model.name}Xpp3WriterEx" )
@@ -29,7 +29,7 @@
 #
 #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};
 
diff --git a/maven-toolchain-model/src/main/mdo/writer.vm b/src/mdo/writer.vm
similarity index 99%
rename from maven-toolchain-model/src/main/mdo/writer.vm
rename to src/mdo/writer.vm
index 7b2c805d3607..aa754b73dae1 100644
--- a/maven-toolchain-model/src/main/mdo/writer.vm
+++ b/src/mdo/writer.vm
@@ -16,7 +16,7 @@
   specific language governing permissions and limitations
   under the License.
 *#
-#parse ( "src/main/mdo/common.vm" )
+#parse ( "common.vm" )
 #
 #set ( $package = "${packageToolV4}" )
 #set ( $className = "${model.name}Xpp3Writer" )
@@ -29,7 +29,7 @@
 #
 #MODELLO-VELOCITY#SAVE-OUTPUT-TO ${package.replace('.','/')}/${className}.java
 // =================== DO NOT EDIT THIS FILE ====================
-//   ${generatedBy}
+//  Generated by Modello Velocity from ${template} template, any modifications will be overwritten.
 // ==============================================================
 package ${package};