[OLINGO-499][OLINGO-501] Serialization of complex collections works properly

Signed-off-by: Michael Bolz <michael.bolz@sap.com>

lib/server-core/src/main/java/org/apache/olingo/server/core/serializer/json/ODataJsonSerializer.java

@@ -370,7 +370,7 @@ public class ODataJsonSerializer implements ODataSerializer {
         writeComplexValue(type, ((LinkedComplexValue) value).getValue(), selectedPaths, json);
         break;
       case COLLECTION_COMPLEX:
-        writeComplexValue(type, property.asComplex(), selectedPaths, json);
+        writeComplexValue(type, ((Property) value).asComplex(), selectedPaths, json);
         break;
       default:
         throw new SerializerException("Property type not yet supported!",

lib/server-core/src/test/java/org/apache/olingo/server/core/serializer/json/ComplexTypeHelper.java

@@ -0,0 +1,66 @@
+/*
+ * 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.
+ */
+package org.apache.olingo.server.core.serializer.json;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.olingo.commons.api.ODataException;
+import org.apache.olingo.commons.api.edm.EdmComplexType;
+import org.apache.olingo.commons.api.edm.EdmPrimitiveTypeKind;
+import org.apache.olingo.commons.api.edm.FullQualifiedName;
+import org.apache.olingo.server.api.edm.provider.ComplexType;
+import org.apache.olingo.server.api.edm.provider.EdmProvider;
+import org.apache.olingo.server.api.edm.provider.NavigationProperty;
+import org.apache.olingo.server.api.edm.provider.Property;
+import org.apache.olingo.server.core.edm.provider.EdmComplexTypeImpl;
+import org.apache.olingo.server.core.edm.provider.EdmProviderImpl;
+
+public class ComplexTypeHelper {
+  
+  public static EdmComplexType createType() throws ODataException {
+    EdmProvider provider = mock(EdmProvider.class);
+    EdmProviderImpl edm = new EdmProviderImpl(provider);
+
+    FullQualifiedName baseName = new FullQualifiedName("namespace", "BaseTypeName");
+    ComplexType baseComplexType = new ComplexType();
+    List<Property> baseProperties = new ArrayList<Property>();
+    baseProperties.add(new Property().setName("prop1").setType(EdmPrimitiveTypeKind.String.getFullQualifiedName()));
+    List<NavigationProperty> baseNavigationProperties = new ArrayList<NavigationProperty>();
+    baseNavigationProperties.add(new NavigationProperty().setName("nav1"));
+    baseComplexType.setName("BaseTypeName").setAbstract(false).setOpenType(false).setProperties(baseProperties)
+        .setNavigationProperties(baseNavigationProperties);
+    when(provider.getComplexType(baseName)).thenReturn(baseComplexType);
+
+    FullQualifiedName name = new FullQualifiedName("namespace", "typeName");
+    ComplexType complexType = new ComplexType().setBaseType(baseName);
+    List<Property> properties = new ArrayList<Property>();
+    properties.add(new Property().setName("prop2").setType(EdmPrimitiveTypeKind.String.getFullQualifiedName()));
+    List<NavigationProperty> navigationProperties = new ArrayList<NavigationProperty>();
+    navigationProperties.add(new NavigationProperty().setName("nav2"));
+    complexType.setName("BaseTypeName").setAbstract(false).setOpenType(false).setProperties(properties)
+        .setNavigationProperties(navigationProperties);
+    when(provider.getComplexType(name)).thenReturn(complexType);
+
+    return EdmComplexTypeImpl.getInstance(edm, name, complexType);
+  }
+}

lib/server-core/src/test/java/org/apache/olingo/server/core/serializer/json/ODataJsonSerializerTest.java

@@ -0,0 +1,71 @@
+/*
+ * 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.
+ */
+package org.apache.olingo.server.core.serializer.json;
+
+import static org.junit.Assert.assertEquals;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.olingo.commons.api.ODataException;
+import org.apache.olingo.commons.api.data.ContextURL;
+import org.apache.olingo.commons.api.data.Property;
+import org.apache.olingo.commons.api.data.ValueType;
+import org.apache.olingo.commons.api.format.ODataFormat;
+import org.apache.olingo.commons.core.data.PropertyImpl;
+import org.apache.olingo.server.api.serializer.ComplexSerializerOptions;
+import org.junit.Test;
+
+public class ODataJsonSerializerTest {
+  @Test
+  public void testCollectionComplex() throws ODataException, IOException {
+    final List<Property> col = new ArrayList<Property>();
+    col.add(new PropertyImpl(null, "ComplexOne", ValueType.COMPLEX, getValues(1)));
+    col.add(new PropertyImpl(null, "ComplexTwo", ValueType.COMPLEX, getValues(2)));
+    final Property complexCollection = new PropertyImpl(null, "ComplexCol", ValueType.COLLECTION_COMPLEX, col);
+    
+    final ODataJsonSerializer serializer = new ODataJsonSerializer(ODataFormat.APPLICATION_JSON);
+    final ComplexSerializerOptions options = ComplexSerializerOptions.with()
+        .contextURL(ContextURL.with().selectList("ComplexCollection").build()).build();
+    final InputStream in = serializer.complexCollection(ComplexTypeHelper.createType(), complexCollection, options);
+    final BufferedReader reader = new BufferedReader(new InputStreamReader(in));
+
+    String line;
+    while ((line = reader.readLine()) != null) {
+      if (line.contains("value")) {
+        assertEquals("{\"@odata.context\":\"$metadata(ComplexCollection)\",\"value\":"
+            + "[{\"prop1\":\"test1\",\"prop2\":\"test11\"},{\"prop1\":\"test2\",\"prop2\":\"test22\"}]}", line);
+      }
+    }
+
+  }
+
+  private List<Property> getValues(int i) {
+    final List<Property> values = new ArrayList<Property>();
+
+    values.add(new PropertyImpl(null, "prop1", ValueType.PRIMITIVE, "test" + i));
+    values.add(new PropertyImpl(null, "prop2", ValueType.PRIMITIVE, "test" + i + i));
+
+    return values;
+  }
+}