Add support for using java.util.Date in communications (#13073)

This adds support for using separate serializer classes on the
server side, similarly to on the client side. Still it is not
public API yet as you do not have the possibility to add your
own serializers to the map used by JsonCodec.

Change-Id: I2cc4f628c5a8eba90abbd57c128c6359cbe1b4d7

3 files changed, 133 insertions, 0 deletions

diff --git a/server/src/com/vaadin/server/JsonCodec.java b/server/src/com/vaadin/server/JsonCodec.java
index d533ed99f3..129307e5c1 100644
--- a/server/src/com/vaadin/server/JsonCodec.java
+++ b/server/src/com/vaadin/server/JsonCodec.java
@@ -31,6 +31,7 @@ import java.lang.reflect.WildcardType;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Date;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -45,6 +46,8 @@ import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 
+import com.vaadin.server.communication.DateSerializer;
+import com.vaadin.server.communication.JSONSerializer;
 import com.vaadin.shared.Connector;
 import com.vaadin.shared.JsonConstants;
 import com.vaadin.shared.communication.UidlValue;
@@ -176,6 +179,11 @@ public class JsonCodec implements Serializable {
      */
     private static Map<String, Class<?>> transportTypeToType = new HashMap<String, Class<?>>();
 
+    private static Map<Class<?>, JSONSerializer<?>> customSerializers = new HashMap<Class<?>, JSONSerializer<?>>();
+    static {
+        customSerializers.put(Date.class, new DateSerializer());
+    }
+
     static {
         registerType(String.class, JsonConstants.VTYPE_STRING);
         registerType(Connector.class, JsonConstants.VTYPE_CONNECTOR);
@@ -283,6 +291,9 @@ public class JsonCodec implements Serializable {
             Class<?> classForType = getClassForType(targetType);
             return decodeEnum(classForType.asSubclass(Enum.class),
                     (String) value);
+        } else if (customSerializers.containsKey(getClassForType(targetType))) {
+            return customSerializers.get(getClassForType(targetType))
+                    .deserialize(targetType, value, connectorTracker);
         } else {
             return decodeObject(targetType, (JSONObject) value,
                     connectorTracker);
@@ -676,6 +687,10 @@ public class JsonCodec implements Serializable {
             return encodeEnum((Enum<?>) value, connectorTracker);
         } else if (value instanceof JSONArray || value instanceof JSONObject) {
             return new EncodeResult(value);
+        } else if (customSerializers.containsKey(value.getClass())) {
+            JSONSerializer serializer = customSerializers.get(value.getClass());
+            return new EncodeResult(serializer.serialize(value,
+                    connectorTracker));
         } else if (valueType instanceof Class<?>) {
             // Any object that we do not know how to encode we encode by looping
             // through fields
diff --git a/server/src/com/vaadin/server/communication/DateSerializer.java b/server/src/com/vaadin/server/communication/DateSerializer.java
new file mode 100644
index 0000000000..9179eb922b
--- /dev/null
+++ b/server/src/com/vaadin/server/communication/DateSerializer.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2000-2013 Vaadin Ltd.
+ * 
+ * Licensed 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 com.vaadin.server.communication;
+
+import java.lang.reflect.Type;
+import java.util.Date;
+
+import com.vaadin.ui.ConnectorTracker;
+
+/**
+ * Server side serializer/deserializer for java.util.Date
+ * 
+ * @since 7.2
+ * @author Vaadin Ltd
+ */
+public class DateSerializer implements JSONSerializer<Date> {
+
+    @Override
+    public Date deserialize(Type type, Object jsonValue,
+            ConnectorTracker connectorTracker) {
+        return new Date(Long.valueOf(String.valueOf(jsonValue)));
+    }
+
+    @Override
+    public Object serialize(Date value, ConnectorTracker connectorTracker) {
+        return value.getTime();
+    }
+
+}
diff --git a/server/src/com/vaadin/server/communication/JSONSerializer.java b/server/src/com/vaadin/server/communication/JSONSerializer.java
new file mode 100644
index 0000000000..603942db61
--- /dev/null
+++ b/server/src/com/vaadin/server/communication/JSONSerializer.java
@@ -0,0 +1,76 @@
+/*
+ * Copyright 2000-2013 Vaadin Ltd.
+ * 
+ * Licensed 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 com.vaadin.server.communication;
+
+import java.lang.reflect.Type;
+
+import com.google.gwt.json.client.JSONValue;
+import com.vaadin.client.ApplicationConnection;
+import com.vaadin.ui.ConnectorTracker;
+
+/**
+ * Implementors of this interface knows how to serialize an Object of a given
+ * type to JSON and how to deserialize the JSON back into an object.
+ * <p>
+ * The {@link #serialize(Object, ApplicationConnection)} and
+ * {@link #deserialize(Type, JSONValue, ApplicationConnection)} methods must be
+ * symmetric so they can be chained and produce the original result (or an equal
+ * result).
+ * <p>
+ * Each {@link JSONSerializer} implementation can handle an object of a single
+ * type.
+ * <p>
+ * This is the server side interface, see
+ * com.vaadin.client.communication.JSONSerializer for the client side interface.
+ * 
+ * @since 7.2
+ * @author Vaadin Ltd
+ */
+public interface JSONSerializer<T> {
+    /**
+     * Creates and deserializes an object received from the client. Must be
+     * compatible with {@link #serialize(Object, ConnectorTracker)} and also
+     * with the client side
+     * {@link com.vaadin.client.communication.JSONSerializer#serialize(Object, ApplicationConnection)}
+     * method.
+     * <p>
+     * The json parameter is of type Object as org.json JSON classes have no
+     * other common super class
+     * 
+     * @param type
+     *            The expected return type
+     * @param jsonValue
+     *            the value from the JSON
+     * @param connectorTracker
+     *            the connector tracker instance for the UI
+     * @return A deserialized object
+     */
+    T deserialize(Type type, Object jsonValue, ConnectorTracker connectorTracker);
+
+    /**
+     * Serialize the given object into JSON. Must be compatible with
+     * {@link #deserialize(Object, connectorTracker)} and the client side
+     * com.vaadin.client.communication.JSONSerializer
+     * 
+     * @param value
+     *            The object to serialize
+     * @param connectorTracker
+     *            The connector tracker instance for the UI
+     * @return A JSON serialized version of the object
+     */
+    Object serialize(T value, ConnectorTracker connectorTracker);
+
+}