Order By Query Clauses Test

src/main/java/org/javawebstack/orm/query/Query.java

@@ -296,20 +296,43 @@ public Query<T> search(String search) {
         return this;
     }
 
-    public Query<T> order(String orderBy) {
-        return order(orderBy, false);
-    }
-
-    public Query<T> order(String orderBy, boolean desc) {
-        return order(new QueryColumn(orderBy), desc);
-    }
-
-    public Query<T> order(QueryColumn orderBy, boolean desc) {
-        boolean success = this.order.add(orderBy, desc);
+    /**
+     * Sorts the results by the given column name ascendingly.
+     *
+     * @param columnName The name of the column to sort ascendingly by.
+     * @return The Query object with the given order by information added.
+     * @throws ORMQueryException if the order operation is called twice on a column specification with the same name.
+     */
+    public Query<T> order(String columnName) throws ORMQueryException {
+        return order(columnName, false);
+    }
+
+    /**
+     * Sorts the results by the given column name with the given order direction.
+     *
+     * @param columnName The name of the column to sort ascendingly by.
+     * @param desc If true it will order descendingly, if false it will order ascendingly.
+     * @return The Query object with the given order by information added.
+     * @throws ORMQueryException if the order operation is called twice on a column specification with the same name.
+     */
+    public Query<T> order(String columnName, boolean desc) throws ORMQueryException {
+        return order(new QueryColumn(columnName), desc);
+    }
+
+    /**
+     * Sorts the results by the given column  with the given order direction.
+     *
+     * @param column The column encoded as QueryColumn object.
+     * @param desc If true it will order descendingly, if false it will order ascendingly.
+     * @return The Query object with the given order by information added.
+     * @throws ORMQueryException if the order operation is called twice on a column specification with the same name.
+     */
+    public Query<T> order(QueryColumn column, boolean desc) throws ORMQueryException{
+        boolean success = this.order.add(column, desc);
         if(!success) {
             throw new ORMQueryException(String.format(
                 "The column %s could not be ordered %s. This is probably caused by calling .order() on this column twice.",
-                orderBy.toString(),
+                column.toString(),
                 desc ? "descendingly" : "ascendingly"
             ));
         }

src/main/java/org/javawebstack/orm/query/QueryOrderBy.java

@@ -1,19 +1,48 @@
 package org.javawebstack.orm.query;
 
+import org.javawebstack.orm.TableInfo;
+
 import java.util.LinkedList;
-import java.util.List;
+import java.util.stream.Collectors;
 
+/**
+ * The QueryOrderBy class serves as an aggregation of order by elements. It extends a list, because the order of the
+ * order by statements is of relevance.
+ */
 public class QueryOrderBy extends LinkedList<QueryOrderByElement>{
 
+    /**
+     * Add a new order by statement. If a statement with the same column name already exists it will not add the
+     * statement.
+     *
+     * @param columnName The column name to order by.
+     * @param desc If the column should be order descendingly.
+     * @return True if adding the statement was successful. False otherwise.
+     */
     public boolean add(String columnName, boolean desc) {
         return this.add(new QueryColumn(columnName), desc);
     }
 
+    /**
+     * Add a new order by statement. If a statement with the same column name already exists it will not add the
+     * statement.
+     *
+     * @param column The column to be ordered by. It will retrieve the name from the QueryColumn.
+     * @param desc If the column should be order descendingly.
+     * @return True if adding the statement was successful. False otherwise.
+     */
     public boolean add(QueryColumn column, boolean desc) {
         return this.add(new QueryOrderByElement(column, desc));
     }
 
     @Override
+    /**
+     * Add a new order by statement. If a statement with the same column name already exists it will not add the
+     * statement.
+     *
+     * @param element The direct QueryOrderByElement which encodes the order by statement.
+     * @return True if adding the statement was successful. False otherwise.
+     */
     public boolean add(QueryOrderByElement element) {
         boolean hasBeenAdded = false;
         if(!willOverwrite(element))
@@ -25,4 +54,17 @@ public boolean add(QueryOrderByElement element) {
     private boolean willOverwrite(QueryOrderByElement element) {
         return this.stream().anyMatch(element::hasEqualColumn);
     }
+
+
+    // The toString methods are specific to MySQL so they might have to be replaced later on.
+    @Override
+    public String toString() {
+        return toString(null);
+    }
+
+    public String toString(TableInfo info) {
+        return this.stream()
+                .map(QueryOrderByElement::toString)
+                .collect(Collectors.joining(","));
+    }
 }

src/main/java/org/javawebstack/orm/query/QueryOrderByElement.java

@@ -1,10 +1,15 @@
 package org.javawebstack.orm.query;
 
+import org.javawebstack.orm.TableInfo;
+
 import java.util.Objects;
 
+/**
+ * The QueryOrderByElement class encodes an Order By Statement.
+ */
 public class QueryOrderByElement {
-    private QueryColumn queryColumn;
-    private boolean desc;
+    private final QueryColumn queryColumn;
+    private final boolean desc;
 
     QueryOrderByElement(String columnName, boolean desc) {
         queryColumn = new QueryColumn(columnName);
@@ -16,28 +21,37 @@ public class QueryOrderByElement {
         this.desc = desc;
     }
 
+    /**
+     * Retrieves the QueryColumn of the statement which encodes the column name.
+     *
+     * @return The encoding QueryColumn object.
+     */
     public QueryColumn getQueryColumn() {
         return queryColumn;
     }
 
+    /**
+     * Retrieves the information if this column is ordered ascendingly or descendingly.
+     *
+     * @return false if ascending, true if descending.
+     */
     public boolean isDesc() {
         return desc;
     }
 
+    /**
+     * Compares the encoded column name.
+     *
+     * @param o An object to compare to.
+     * @return True if the object is a QueryOrderByElement with a QueryColumn with generates the same identifier.
+     */
     public boolean hasEqualColumn(Object o) {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
         QueryOrderByElement that = (QueryOrderByElement) o;
         return getQueryColumn().equals(that.getQueryColumn());
     }
 
-    public boolean hasEqualOrderDirection(Object o) {
-        if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
-        QueryOrderByElement that = (QueryOrderByElement) o;
-        return isDesc() == that.isDesc();
-    }
-
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
@@ -50,4 +64,17 @@ public boolean equals(Object o) {
     public int hashCode() {
         return Objects.hash(getQueryColumn(), isDesc());
     }
+
+    @Override
+    public String toString() {
+        return this.toString(null);
+    }
+
+    public String toString(TableInfo info) {
+        String stringifiedOrderBy = getQueryColumn().toString(info);
+        if (isDesc())
+            stringifiedOrderBy += " DESC";
+
+        return stringifiedOrderBy;
+    }
 }

src/main/java/org/javawebstack/orm/wrapper/builder/MySQLQueryStringBuilder.java

@@ -50,11 +50,13 @@ public SQLQueryString buildQuery(Query<?> query, boolean count) {
             sb.append(" WHERE ").append(qs.getQuery());
             parameters.addAll(qs.getParameters());
         }
-        if (query.getOrder() != null) {
-            sb.append(" ORDER BY ").append(query.getOrder().toString(repo.getInfo()));
-            if (query.isDescOrder())
-                sb.append(" DESC");
+
+        QueryOrderBy orderBy = query.getOrder();
+        if (!orderBy.isEmpty()) {
+            sb.append(" ORDER BY ")
+                .append(orderBy.toString());
         }
+
         Integer offset = query.getOffset();
         Integer limit = query.getLimit();
         if (offset != null && limit == null)

src/test/java/org/javawebstack/orm/test/exception/SectionIndexOutOfBoundException.java

@@ -0,0 +1,17 @@
+package org.javawebstack.orm.test.exception;
+
+import lombok.Getter;
+import lombok.Setter;
+
+@Getter
+@Setter
+/**
+ * Only to be used for tests.
+ * This exception should be thrown when a SQL Query String is manually parsed and sections and section types are defined, and
+ * a type of section is attempted to be retrieved which does not exist in this number.
+ */
+public class SectionIndexOutOfBoundException extends Exception {
+    private int sectionCount;
+    private int attemptedIndex;
+    private String topLevelKeyword;
+}

src/test/java/org/javawebstack/orm/test/querybuilding/OrderByClauseTest.java

@@ -0,0 +1,156 @@
+package org.javawebstack.orm.test.querybuilding;
+
+import org.javawebstack.orm.exception.ORMQueryException;
+import org.javawebstack.orm.query.Query;
+import org.javawebstack.orm.test.exception.SectionIndexOutOfBoundException;
+import org.javawebstack.orm.test.shared.models.Datatype;
+import org.javawebstack.orm.test.shared.verification.QueryVerification;
+import org.junit.jupiter.api.Test;
+
+import javax.xml.crypto.Data;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+import static org.javawebstack.orm.test.shared.setup.ModelSetup.setUpModel;
+import static org.junit.jupiter.api.Assertions.*;
+
+// This class tests the query generation for order by statements an MySQL
+public class OrderByClauseTest {
+
+    @Test
+    void testOneExistingColumnDefaultOrderBy() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("wrapper_integer");
+        new QueryVerification(query).assertSectionEquals("ORDER BY", "`wrapper_integer`");
+    }
+
+    @Test
+    void testOneNonExistingColumnDefaultOrderBy() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("does_not_exist");
+        new QueryVerification(query).assertSectionEquals("ORDER BY", "`does_not_exist`");
+    }
+
+    @Test
+    void testOneExistingColumnASCOrderBy() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("wrapper_integer", false);
+        new QueryVerification(query).assertSectionEquals("ORDER BY", "`wrapper_integer`");
+    }
+
+    @Test
+    void testOneNonExistingColumnASCOrderBy() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("does_not_exist", false);
+        new QueryVerification(query).assertSectionEquals("ORDER BY", "`does_not_exist`");
+    }
+
+    @Test
+    void testOneExistingColumnDESCOrderBy() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("wrapper_integer", true);
+        new QueryVerification(query).assertSectionEquals("ORDER BY", "`wrapper_integer` DESC");
+    }
+
+    @Test
+    void testOneNonExistingColumnDESCOrderBy() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("does_not_exist", true);
+        new QueryVerification(query).assertSectionEquals("ORDER BY", "`does_not_exist` DESC");
+    }
+
+    @Test
+    void testMultipleOrderByClausesOfASCOrder() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("wrapper_integer")
+                .order("primitive_integer");
+
+        new QueryVerification(query)
+                .assertSectionContains("ORDER BY", "`wrapper_integer`")
+                .assertSectionContains("ORDER BY", "`primitive_integer`");
+    }
+
+    @Test
+    void testMultipleOrderByClausesOfDESCOrder() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("wrapper_integer", true)
+                .order("primitive_integer", true);
+
+        new QueryVerification(query)
+                .assertSectionContains("ORDER BY", "`wrapper_integer` DESC")
+                .assertSectionContains("ORDER BY", "`primitive_integer` DESC");
+    }
+
+    @Test
+    void testMultipleOrderByClausesOfMixedOrder() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("wrapper_integer", false)
+                .order("primitive_integer", true);
+
+        new QueryVerification(query)
+                .assertSectionContains("ORDER BY", "`wrapper_integer`")
+                .assertSectionContains("ORDER BY", "`primitive_integer` DESC");
+    }
+
+    @Test
+    void testMultipleOrderByClausesOfMixedOrderReversed() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("primitive_integer", true)
+                .order("wrapper_integer", false);
+
+        new QueryVerification(query)
+                .assertSectionContains("ORDER BY", "`primitive_integer` DESC")
+                .assertSectionContains("ORDER BY", "`wrapper_integer`");
+    }
+
+
+    @Test
+    // This test is important because putting the order by statements in different order is relevant (they set priorities)
+    void testMultipleOrderByClausesOfRandomOrderForCorrectOrder() throws SectionIndexOutOfBoundException {
+        Query<Datatype> query = setUpModel(Datatype.class).query();
+        ArrayList<String> columnNames = new ArrayList<>(Datatype.columnNames);
+
+        LinkedList<String> callOrder = new LinkedList<>();
+
+        Random r = new Random();
+        columnNames.stream().unordered().forEach((singleColumn) -> {
+            query.order(singleColumn, r.nextBoolean());
+            callOrder.add(singleColumn);
+        });
+
+        String queryString = new QueryVerification(query).getSection("ORDER BY");
+        int lastIndex = 0;
+        int foundIndex = -1;
+        for (String nextInCallOrder : callOrder) {
+            foundIndex = queryString.indexOf("`" + nextInCallOrder + "`");
+            if(foundIndex < lastIndex) {
+                if (foundIndex == -1)
+                    fail("Not all columns occurred in the query string.");
+                else
+                    fail("The columns did not appear an the correct order.");
+
+                break;
+            }
+
+            lastIndex = foundIndex;
+        }
+
+        // If it came until here the test should count as passed.
+        assertTrue(true);
+
+    }
+
+    /*
+     * Error Cases
+     */
+
+    // This test might not be correct here as it does not purely look at the query
+    @Test
+    void testCannotCallOrderOnSameColumnTwice() {
+        Query<Datatype> query = setUpModel(Datatype.class).query()
+                .order("primitive_integer", true);
+
+        assertThrows(ORMQueryException.class, () -> query.order("primitive_integer"));
+    }
+}