Increased unit tests coverage.

Author: PrimosK

src/main/java/com/microsoft/graph/serializer/FallbackTypeAdapterFactory.java

@@ -24,10 +24,8 @@
 
 import com.google.common.base.CaseFormat;
 import com.google.gson.Gson;
-import com.google.gson.JsonElement;
 import com.google.gson.TypeAdapter;
 import com.google.gson.TypeAdapterFactory;
-import com.google.gson.internal.Streams;
 import com.google.gson.internal.bind.ReflectiveTypeAdapterFactory;
 import com.google.gson.reflect.TypeToken;
 import com.google.gson.stream.JsonReader;
@@ -105,58 +103,13 @@ public <T> TypeAdapter<T> create(@Nonnull final Gson gson, @Nonnull final TypeTo
                 return null;
             }
 
-            return (TypeAdapter<T>) new ODataTypeParametrizedIJsonBackedObjectAdapter(gson, delegatedAdapter, (TypeToken<IJsonBackedObject>) type, logger);
+            return (TypeAdapter<T>) new ODataTypeParametrizedIJsonBackedTypedAdapter(this, gson, delegatedAdapter, (TypeToken<IJsonBackedObject>) type, logger);
         }
         else {
             return null;
         }
     }
 
-    /**
-     * This adapter is responsible for deserialization of IJsonBackedObjects where service
-     * returns one of several derived types of a base object, which is defined using the
-     * odata.type parameter. If odata.type parameter is not found, the Gson default
-     * (delegated) type adapter is used.
-     */
-    private class ODataTypeParametrizedIJsonBackedObjectAdapter extends TypeAdapter<IJsonBackedObject> {
-
-        private final Gson gson;
-        private final TypeAdapter<IJsonBackedObject> delegatedAdapter;
-        private final TypeToken<IJsonBackedObject> type;
-        private final DerivedClassIdentifier derivedClassIdentifier;
-
-        public ODataTypeParametrizedIJsonBackedObjectAdapter(@Nonnull Gson gson, @Nonnull TypeAdapter<IJsonBackedObject> delegatedAdapter, @Nonnull final TypeToken<IJsonBackedObject> type, @Nonnull final ILogger logger) {
-            super();
-            this.gson = Objects.requireNonNull(gson, "parameter gson cannot be null");
-            this.delegatedAdapter = Objects.requireNonNull(delegatedAdapter, "object delegated adapted cannot be null");
-            this.type = Objects.requireNonNull(type, "object type cannot be null");
-            this.derivedClassIdentifier = new DerivedClassIdentifier(logger);
-        }
-
-        @Override
-        public void write(JsonWriter out, IJsonBackedObject value)
-            throws IOException
-        {
-            this.delegatedAdapter.write(out, value);
-        }
-
-        @Override
-        public IJsonBackedObject read(JsonReader in) {
-            JsonElement jsonElement = Streams.parse(in);
-
-            if (jsonElement.isJsonObject()) {
-                final Class<?> derivedClass = derivedClassIdentifier.identify(jsonElement.getAsJsonObject(), type.getRawType());
-
-                if (derivedClass != null) {
-                    final TypeAdapter<?> subTypeAdapter = gson.getDelegateAdapter(FallbackTypeAdapterFactory.this, TypeToken.get(derivedClass));
-                    return (IJsonBackedObject) subTypeAdapter.fromJsonTree(jsonElement);
-                }
-            }
-
-            return delegatedAdapter.fromJsonTree(jsonElement);
-        }
-    }
-
     private static final class EnumTypeAdapter<T> extends TypeAdapter<T> {
 
         private final Map<String, T> enumValues;

src/test/java/com/microsoft/graph/models/MessageStub.java

@@ -10,9 +10,9 @@
  */
 public class MessageStub extends TestIJsonBackedObject {
 
-    @SerializedName("name")
+    @SerializedName("body")
     @Expose()
-    public String name;
+    public String body;
 
     @SerializedName("reaction")
     @Expose()

src/test/java/com/microsoft/graph/models/ReactionsStub.java

@@ -0,0 +1,21 @@
+package com.microsoft.graph.models;
+
+import com.google.gson.annotations.Expose;
+import com.google.gson.annotations.SerializedName;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+
+/**
+ * This class shouldn't be moved as it's location in this
+ * particular package is tightly coupled with the logic present at:
+ * com/microsoft/graph/serializer/DerivedClassIdentifier.java:38
+ */
+public class ReactionsStub extends TestIJsonBackedObject {
+
+    @SerializedName("reactions")
+    @Expose
+    @Nullable
+    public List<ReactionStub> reactions;
+
+}

src/test/java/com/microsoft/graph/serializer/FallbackTypeAdapterFactoryTest.java

@@ -0,0 +1,101 @@
+package com.microsoft.graph.serializer;
+
+import com.google.gson.Gson;
+import com.google.gson.reflect.TypeToken;
+import com.microsoft.graph.http.BaseCollectionResponse;
+import com.microsoft.graph.logger.ILogger;
+import com.microsoft.graph.models.MessageStub;
+import com.microsoft.graph.models.MessagesCollectionResponseStub;
+import com.microsoft.graph.models.ReactionStub;
+import com.microsoft.graph.models.ReactionsStub;
+import com.microsoft.graph.models.SubReactionStub1;
+import com.microsoft.graph.models.SubReactionStub2;
+import org.junit.jupiter.api.Test;
+
+import java.lang.reflect.Type;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Covers the scenario of objects not being properly deserialized
+ * (@odata.type not taken into account):
+ * https://github.com/microsoftgraph/msgraph-sdk-java-core/pull/249
+ */
+public class ODataTypeParametrizedIJsonBackedTypedAdapterTest {
+
+    final ILogger logger = mock(ILogger.class);
+    final Gson gsonInstance = GsonFactory.getGsonInstance(logger);
+
+    @Test
+    public void testDeserializationOfObjectWithODataTypeProperty() {
+        // Given
+        final String testJsonResponse =
+            "{\"@odata.type\": \"#microsoft.graph.subReactionStub1\"}";
+
+        // When
+        ReactionStub reaction = gsonInstance.fromJson(testJsonResponse, ReactionStub.class);
+
+        // Then
+        assertTrue(reaction instanceof SubReactionStub1);
+    }
+
+    @Test
+    public void testDeserializationOfPropertyWithODataTypeProperty() {
+        // Given
+        final String testJsonResponse =
+            "{\"body\": \"message1\",\"reaction\": {\"@odata.type\": \"#microsoft.graph.subReactionStub2\"}}";
+
+        // When
+        MessageStub message = gsonInstance.fromJson(testJsonResponse, MessageStub.class);
+
+        // Then
+        assertTrue(message.reaction instanceof SubReactionStub2);
+    }
+
+    @Test
+    public void testDeserializationOfCollectionPropertyContainingObjectsWithODataTypeProperty() {
+        // Given
+        final String testJsonResponse =
+            "{ reactions : [" +
+                "{\"@odata.type\": \"#microsoft.graph.subReactionStub1\"}," +
+                "{\"@odata.type\": \"#microsoft.graph.subReactionStub2\"}," +
+                "{\"@odata.type\": \"#microsoft.graph.subReactionStub1\"}," +
+            "]}";
+
+        // When
+        ReactionsStub reactions = gsonInstance.fromJson(testJsonResponse, ReactionsStub.class);
+
+        // Then
+        assertNotNull(reactions.reactions);
+        assertTrue(reactions.reactions.get(0) instanceof SubReactionStub1);
+        assertTrue(reactions.reactions.get(1) instanceof SubReactionStub2);
+        assertTrue(reactions.reactions.get(2) instanceof SubReactionStub1);
+    }
+
+    @Test
+    public void testDeserializationOfNestedODataTypeAnnotatedObjects() {
+        // Given
+        final Type listType = new TypeToken<MessagesCollectionResponseStub>(){}.getType();
+        final String testJsonResponse =
+            "{\"value\": " +
+            "  [" +
+            "    {\"body\": \"message1\",\"reaction\": {\"@odata.type\": \"#microsoft.graph.subReactionStub1\"}}," +
+            "    {\"body\": \"message2\",\"reaction\": {\"@odata.type\": \"#microsoft.graph.subReactionStub2\"}}" +
+            "  ]" +
+            "}";
+
+        // When
+        final BaseCollectionResponse<MessageStub> baseCollectionResponse = gsonInstance.fromJson(testJsonResponse, listType);
+
+        // Then
+        assertNotNull(baseCollectionResponse.value);
+
+        final MessageStub messageStub1 = baseCollectionResponse.value.get(0);
+        final MessageStub messageStub2 = baseCollectionResponse.value.get(1);
+
+        assertTrue(messageStub1.reaction instanceof SubReactionStub1);
+        assertTrue(messageStub2.reaction instanceof SubReactionStub2);
+    }
+}