Support for Empty namespace name for java classes without package

tools/generator/Java.Interop.Tools.Generator.CodeGeneration/CodeGenerator.cs

@@ -522,8 +522,13 @@ public void WriteInterfaceDeclaration (InterfaceGen @interface, string indent)
 			if (@interface.IsDeprecated)
 				writer.WriteLine ("{0}[ObsoleteAttribute (@\"{1}\")]", indent, @interface.DeprecatedComment);
 
-			if (!@interface.IsConstSugar)
-				writer.WriteLine ("{0}[Register (\"{1}\", \"\", \"{2}\"{3})]", indent, @interface.RawJniName, @interface.Namespace + "." + @interface.FullName.Substring (@interface.Namespace.Length + 1).Replace ('.', '/') + "Invoker", @interface.AdditionalAttributeString ());
+			if (!@interface.IsConstSugar) {
+				var signature = string.IsNullOrWhiteSpace (@interface.Namespace)
+					? @interface.FullName.Replace ('.', '/')
+					: @interface.Namespace + "." + @interface.FullName.Substring (@interface.Namespace.Length + 1).Replace ('.', '/');
+
+				writer.WriteLine ("{0}[Register (\"{1}\", \"\", \"{2}\"{3})]", indent, @interface.RawJniName, signature + "Invoker", @interface.AdditionalAttributeString ());
+			}
 
 			if (@interface.TypeParameters != null && @interface.TypeParameters.Any ())
 				writer.WriteLine ("{0}{1}", indent, @interface.TypeParameters.ToGeneratedAttributeString ());

tools/generator/Java.Interop.Tools.Generator.Importers/XmlApiImporter.cs

@@ -131,7 +131,7 @@ public static GenBaseSupport CreateGenBaseSupport (XElement pkg, XElement elem,
 				PackageName = pkg.XGetAttribute ("name"),
 				Visibility = elem.XGetAttribute ("visibility")
 			};
-			
+
 			if (support.IsDeprecated) {
 				support.DeprecatedComment = elem.XGetAttribute ("deprecated");
 
@@ -165,7 +165,7 @@ public static GenBaseSupport CreateGenBaseSupport (XElement pkg, XElement elem,
 
 			if (elem.Attribute ("managedName") != null) {
 				support.Name = elem.XGetAttribute ("managedName");
-				support.FullName = string.Format ("{0}.{1}", support.Namespace, support.Name);
+				support.FullName = string.IsNullOrWhiteSpace(support.Namespace) ? support.Name : $"{support.Namespace}.{support.Name}";
 				int idx = support.Name.LastIndexOf ('.');
 				support.Name = idx > 0 ? support.Name.Substring (idx + 1) : support.Name;
 				raw_name = support.Name;
@@ -177,7 +177,9 @@ public static GenBaseSupport CreateGenBaseSupport (XElement pkg, XElement elem,
 				raw_name = support.Name;
 				support.TypeNamePrefix = isInterface ? IsPrefixableName (raw_name) ? "I" : string.Empty : string.Empty;
 				support.Name = EnsureValidIdentifer (support.TypeNamePrefix + raw_name);
-				support.FullName = string.Format ("{0}.{1}{2}", support.Namespace, idx > 0 ? StringRocks.TypeToPascalCase (support.JavaSimpleName.Substring (0, idx + 1)) : string.Empty, support.Name);
+				var supportNamespace = string.IsNullOrWhiteSpace (support.Namespace) ? string.Empty : $"{support.Namespace}.";
+				var supportSimpleName = idx > 0 ? StringRocks.TypeToPascalCase (support.JavaSimpleName.Substring (0, idx + 1)) : string.Empty;
+				support.FullName = string.Format ("{0}{1}{2}", supportNamespace, supportSimpleName, support.Name);
 			}
 
 			support.IsObfuscated = IsObfuscatedName (pkg.Elements ().Count (), support.JavaSimpleName) && elem.XGetAttribute ("obfuscated") != "false";

tools/generator/Java.Interop.Tools.Generator.ObjectModel/ClassGen.cs

@@ -137,13 +137,18 @@ public override void Generate (CodeGenerationOptions opt, GenerationInfo gen_inf
 					sw.WriteLine ("using Java.Interop;");
 				}
 				sw.WriteLine ();
-				sw.WriteLine ("namespace {0} {{", Namespace);
-				sw.WriteLine ();
+				var hasNamespace = !string.IsNullOrWhiteSpace (Namespace);
+				if (hasNamespace) {
+					sw.WriteLine ("namespace {0} {{", Namespace);
+					sw.WriteLine ();
+				}
 
 				var generator = opt.CreateCodeGenerator (sw);
-				generator.WriteClass (this, "\t", gen_info);
+				generator.WriteClass (this, hasNamespace ? "\t" : string.Empty, gen_info);
 
-				sw.WriteLine ("}");
+				if (hasNamespace) {
+					sw.WriteLine ("}");
+				}
 			}
 		}
 

tools/generator/Java.Interop.Tools.Generator.ObjectModel/GenBase.cs

@@ -170,8 +170,9 @@ IEnumerable<GenBase> Ancestors ()
 
 		// not: not currently assembly qualified, but it uses needed
 		// Type.GetType() conventions such as '/' for nested types.
-		public string AssemblyQualifiedName =>
-			$"{Namespace}.{FullName.Substring (Namespace.Length + 1).Replace ('.', '/')}";
+		public string AssemblyQualifiedName => string.IsNullOrWhiteSpace (Namespace)
+			? $"{FullName.Replace ('.', '/')}"
+			: $"{Namespace}." + $"{FullName.Substring (Namespace.Length + 1).Replace ('.', '/')}";
 
 		public int ApiAvailableSince { get; set; }
 
@@ -590,7 +591,9 @@ static bool IsTypeCommensurate (CodeGenerationOptions opt, ISymbol sym)
 
 		public bool IsValid { get; set; } = true;
 
-		public string JavaName => $"{PackageName}.{JavaSimpleName}";
+		public string JavaName => string.IsNullOrWhiteSpace (PackageName)
+			? JavaSimpleName
+			: $"{PackageName}.{JavaSimpleName}";
 
 		public string JavaSimpleName => support.JavaSimpleName;
 
@@ -718,7 +721,7 @@ public string [] PreCallback (CodeGenerationOptions opt, string var_name, bool o
 
 		public string [] PostCallback (CodeGenerationOptions opt, string var_name) => new string [] { };
 
-		public string RawJniName => PackageName.Replace ('.', '/') + "/" + JavaSimpleName.Replace ('.', '$');
+		public string RawJniName => (string.IsNullOrWhiteSpace (PackageName) ? string.Empty : PackageName.Replace ('.', '/') + "/") + JavaSimpleName.Replace ('.', '$');
 
 		public string RawVisibility => support.Visibility;
 

tools/generator/Java.Interop.Tools.Generator.ObjectModel/InterfaceGen.cs

@@ -46,7 +46,7 @@ public override string FromNative (CodeGenerationOptions opt, string varname, bo
 		public override void FixupAccessModifiers (CodeGenerationOptions opt)
 		{
 			if (!IsAnnotation) {
-				foreach (var implementedInterface in ImplementedInterfaces) { 
+				foreach (var implementedInterface in ImplementedInterfaces) {
 					if (string.IsNullOrEmpty (implementedInterface)) {
 						System.Diagnostics.Debug.Assert (false, "BUGBUG - We should never have an empty or null string added on the implemented interface list.");
 						continue;
@@ -62,7 +62,7 @@ public override void FixupAccessModifiers (CodeGenerationOptions opt)
 					}
 				}
 			}
-			
+
 
 			base.FixupAccessModifiers (opt);
 		}
@@ -77,13 +77,18 @@ public override void Generate (CodeGenerationOptions opt, GenerationInfo gen_inf
 					sw.WriteLine ("using Java.Interop;");
 				}
 				sw.WriteLine ();
-				sw.WriteLine ("namespace {0} {{", Namespace);
-				sw.WriteLine ();
+				var hasNamespace = !string.IsNullOrWhiteSpace (Namespace);
+				if (hasNamespace) {
+					sw.WriteLine ("namespace {0} {{", Namespace);
+					sw.WriteLine ();
+				}
 
 				var generator = opt.CreateCodeGenerator (sw);
-				generator.WriteInterface (this, "\t", gen_info);
+				generator.WriteInterface (this, hasNamespace ? "\t" : string.Empty, gen_info);
 
-				sw.WriteLine ("}");
+				if (hasNamespace) {
+					sw.WriteLine ("}");
+				}
 			}
 
 			GenerateAnnotationAttribute (opt, gen_info);

tools/generator/Tests/expected.ji/TestInterface/Mono.Android.projitems

@@ -5,6 +5,8 @@
   </PropertyGroup>
   <!-- Classes -->
   <ItemGroup>
+    <Compile Include="$(MSBuildThisFileDirectory)ClassWithoutNamespace.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)IInterfaceWithoutNamespace.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Java.Interop.__TypeRegistrations.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Java.Lang.Object.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Java.Lang.String.cs" />

tools/generator/Tests/expected.ji/TestInterface/__NamespaceMapping__.cs

@@ -1,2 +1,3 @@
 [assembly:global::Android.Runtime.NamespaceMapping (Java = "java.lang", Managed="Java.Lang")]
 [assembly:global::Android.Runtime.NamespaceMapping (Java = "test.me", Managed="Test.ME")]
+[assembly:global::Android.Runtime.NamespaceMapping (Java = "", Managed="")]

tools/generator/Tests/expected/TestInterface/ClassWithoutNamespace.cs

@@ -0,0 +1,99 @@
+using System;
+using System.Collections.Generic;
+using Android.Runtime;
+
+// Metadata.xml XPath class reference: path="/api/package[@name='']/class[@name='ClassWithoutNamespace']"
+[global::Android.Runtime.Register ("ClassWithoutNamespace", DoNotGenerateAcw=true)]
+public abstract partial class ClassWithoutNamespace : global::Java.Lang.Object, IInterfaceWithoutNamespace {
+
+	internal static new IntPtr java_class_handle;
+	internal static new IntPtr class_ref {
+		get {
+			return JNIEnv.FindClass ("ClassWithoutNamespace", ref java_class_handle);
+		}
+	}
+
+	protected override IntPtr ThresholdClass {
+		get { return class_ref; }
+	}
+
+	protected override global::System.Type ThresholdType {
+		get { return typeof (ClassWithoutNamespace); }
+	}
+
+	protected ClassWithoutNamespace (IntPtr javaReference, JniHandleOwnership transfer) : base (javaReference, transfer) {}
+
+	static IntPtr id_ctor;
+	// Metadata.xml XPath constructor reference: path="/api/package[@name='']/class[@name='ClassWithoutNamespace']/constructor[@name='ClassWithoutNamespace' and count(parameter)=0]"
+	[Register (".ctor", "()V", "")]
+	public unsafe ClassWithoutNamespace ()
+		: base (IntPtr.Zero, JniHandleOwnership.DoNotTransfer)
+	{
+		if (((global::Java.Lang.Object) this).Handle != IntPtr.Zero)
+			return;
+
+		try {
+			if (((object) this).GetType () != typeof (ClassWithoutNamespace)) {
+				SetHandle (
+						global::Android.Runtime.JNIEnv.StartCreateInstance (((object) this).GetType (), "()V"),
+						JniHandleOwnership.TransferLocalRef);
+				global::Android.Runtime.JNIEnv.FinishCreateInstance (((global::Java.Lang.Object) this).Handle, "()V");
+				return;
+			}
+
+			if (id_ctor == IntPtr.Zero)
+				id_ctor = JNIEnv.GetMethodID (class_ref, "<init>", "()V");
+			SetHandle (
+					global::Android.Runtime.JNIEnv.StartCreateInstance (class_ref, id_ctor),
+					JniHandleOwnership.TransferLocalRef);
+			JNIEnv.FinishCreateInstance (((global::Java.Lang.Object) this).Handle, class_ref, id_ctor);
+		} finally {
+		}
+	}
+
+	static Delegate cb_Foo;
+#pragma warning disable 0169
+	static Delegate GetFooHandler ()
+	{
+		if (cb_Foo == null)
+			cb_Foo = JNINativeWrapper.CreateDelegate ((Action<IntPtr, IntPtr>) n_Foo);
+		return cb_Foo;
+	}
+
+	static void n_Foo (IntPtr jnienv, IntPtr native__this)
+	{
+		ClassWithoutNamespace __this = global::Java.Lang.Object.GetObject<ClassWithoutNamespace> (jnienv, native__this, JniHandleOwnership.DoNotTransfer);
+		__this.Foo ();
+	}
+#pragma warning restore 0169
+
+	// Metadata.xml XPath method reference: path="/api/package[@name='']/interface[@name='InterfaceWithoutNamespace']/method[@name='Foo' and count(parameter)=0]"
+	[Register ("Foo", "()V", "GetFooHandler")]
+	public abstract void Foo ();
+
+}
+
+[global::Android.Runtime.Register ("ClassWithoutNamespace", DoNotGenerateAcw=true)]
+internal partial class ClassWithoutNamespaceInvoker : ClassWithoutNamespace {
+
+	public ClassWithoutNamespaceInvoker (IntPtr handle, JniHandleOwnership transfer) : base (handle, transfer) {}
+
+	protected override global::System.Type ThresholdType {
+		get { return typeof (ClassWithoutNamespaceInvoker); }
+	}
+
+	static IntPtr id_Foo;
+	// Metadata.xml XPath method reference: path="/api/package[@name='']/interface[@name='InterfaceWithoutNamespace']/method[@name='Foo' and count(parameter)=0]"
+	[Register ("Foo", "()V", "GetFooHandler")]
+	public override unsafe void Foo ()
+	{
+		if (id_Foo == IntPtr.Zero)
+			id_Foo = JNIEnv.GetMethodID (class_ref, "Foo", "()V");
+		try {
+			JNIEnv.CallVoidMethod (((global::Java.Lang.Object) this).Handle, id_Foo);
+		} finally {
+		}
+	}
+
+}
+

tools/generator/Tests/expected/TestInterface/IInterfaceWithoutNamespace.cs

@@ -0,0 +1,83 @@
+using System;
+using System.Collections.Generic;
+using Android.Runtime;
+
+// Metadata.xml XPath interface reference: path="/api/package[@name='']/interface[@name='InterfaceWithoutNamespace']"
+[Register ("InterfaceWithoutNamespace", "", "IInterfaceWithoutNamespaceInvoker")]
+public partial interface IInterfaceWithoutNamespace : IJavaObject {
+
+	// Metadata.xml XPath method reference: path="/api/package[@name='']/interface[@name='InterfaceWithoutNamespace']/method[@name='Foo' and count(parameter)=0]"
+	[Register ("Foo", "()V", "GetFooHandler:IInterfaceWithoutNamespaceInvoker, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null")]
+	void Foo ();
+
+}
+
+[global::Android.Runtime.Register ("InterfaceWithoutNamespace", DoNotGenerateAcw=true)]
+internal partial class IInterfaceWithoutNamespaceInvoker : global::Java.Lang.Object, IInterfaceWithoutNamespace {
+
+	static IntPtr java_class_ref = JNIEnv.FindClass ("InterfaceWithoutNamespace");
+
+	protected override IntPtr ThresholdClass {
+		get { return class_ref; }
+	}
+
+	protected override global::System.Type ThresholdType {
+		get { return typeof (IInterfaceWithoutNamespaceInvoker); }
+	}
+
+	new IntPtr class_ref;
+
+	public static IInterfaceWithoutNamespace GetObject (IntPtr handle, JniHandleOwnership transfer)
+	{
+		return global::Java.Lang.Object.GetObject<IInterfaceWithoutNamespace> (handle, transfer);
+	}
+
+	static IntPtr Validate (IntPtr handle)
+	{
+		if (!JNIEnv.IsInstanceOf (handle, java_class_ref))
+			throw new InvalidCastException (string.Format ("Unable to convert instance of type '{0}' to type '{1}'.",
+						JNIEnv.GetClassNameFromInstance (handle), "InterfaceWithoutNamespace"));
+		return handle;
+	}
+
+	protected override void Dispose (bool disposing)
+	{
+		if (this.class_ref != IntPtr.Zero)
+			JNIEnv.DeleteGlobalRef (this.class_ref);
+		this.class_ref = IntPtr.Zero;
+		base.Dispose (disposing);
+	}
+
+	public IInterfaceWithoutNamespaceInvoker (IntPtr handle, JniHandleOwnership transfer) : base (Validate (handle), transfer)
+	{
+		IntPtr local_ref = JNIEnv.GetObjectClass (((global::Java.Lang.Object) this).Handle);
+		this.class_ref = JNIEnv.NewGlobalRef (local_ref);
+		JNIEnv.DeleteLocalRef (local_ref);
+	}
+
+	static Delegate cb_Foo;
+#pragma warning disable 0169
+	static Delegate GetFooHandler ()
+	{
+		if (cb_Foo == null)
+			cb_Foo = JNINativeWrapper.CreateDelegate ((Action<IntPtr, IntPtr>) n_Foo);
+		return cb_Foo;
+	}
+
+	static void n_Foo (IntPtr jnienv, IntPtr native__this)
+	{
+		IInterfaceWithoutNamespace __this = global::Java.Lang.Object.GetObject<IInterfaceWithoutNamespace> (jnienv, native__this, JniHandleOwnership.DoNotTransfer);
+		__this.Foo ();
+	}
+#pragma warning restore 0169
+
+	IntPtr id_Foo;
+	public unsafe void Foo ()
+	{
+		if (id_Foo == IntPtr.Zero)
+			id_Foo = JNIEnv.GetMethodID (class_ref, "Foo", "()V");
+		JNIEnv.CallVoidMethod (((global::Java.Lang.Object) this).Handle, id_Foo);
+	}
+
+}
+

tools/generator/Tests/expected/TestInterface/TestInterface.xml

@@ -50,7 +50,7 @@
 			<implements name="test.me.TestInterface" name-generic-aware="test.me.TestInterface" />
 			<constructor deprecated="not deprecated" final="false" name="TestInterfaceImplementation" static="false" visibility="public" />
 		</class>
-		<!-- 
+		<!--
 			public interface GenericInterface<T> {
 				void SetObject(T item);
 			}
@@ -87,7 +87,7 @@
 				<parameter name="value" type="java.lang.String[]" />
 			</method>
 		</class>
-		<!-- 
+		<!--
 			public interface GenericPropertyInterface<T> {
 				T getObject();
 				void setObject(T value);
@@ -138,4 +138,13 @@
 			</method>
 		</class>
 	</package>
+  <package name="">
+    <interface abstract="false" deprecated="not deprecated" extends="java.lang.Object" extends-generic-aware="java.lang.Object" final="false" name="InterfaceWithoutNamespace" static="false" visibility="public">
+      <method abstract="true" deprecated="not deprecated" final="false" name="Foo" native="false" return="void" static="false" synchronized="false" visibility="public" />
+		</interface>
+    <class abstract="true" deprecated="not deprecated" extends="java.lang.Object" extends-generic-aware="java.lang.Object" final="false" name="ClassWithoutNamespace" static="false" visibility="public">
+			<implements name="InterfaceWithoutNamespace" name-generic-aware="InterfaceWithoutNamespace" />
+			<constructor deprecated="not deprecated" final="false" name="ClassWithoutNamespace" static="false" visibility="public" />
+		</class>
+	</package>
 </api>