Adding default type adapter for InetAddress.

gson/src/main/java/com/google/gson/DefaultTypeAdapters.java

@@ -20,10 +20,12 @@ import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
 import java.math.BigDecimal;
 import java.math.BigInteger;
+import java.net.InetAddress;
 import java.net.MalformedURLException;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
+import java.net.UnknownHostException;
 import java.sql.Time;
 import java.sql.Timestamp;
 import java.text.DateFormat;
@@ -68,6 +70,8 @@ final class DefaultTypeAdapters {
   private static final UriTypeAdapter URI_TYPE_ADAPTER = new UriTypeAdapter();
   private static final UuidTypeAdapter UUUID_TYPE_ADAPTER = new UuidTypeAdapter();
   private static final LocaleTypeAdapter LOCALE_TYPE_ADAPTER = new LocaleTypeAdapter();
+  private static final DefaultInetAddressAdapter INET_ADDRESS_ADAPTER =
+      new DefaultInetAddressAdapter();
   private static final CollectionTypeAdapter COLLECTION_TYPE_ADAPTER = new CollectionTypeAdapter();
   private static final MapTypeAdapter MAP_TYPE_ADAPTER = new MapTypeAdapter();
   private static final BigDecimalTypeAdapter BIG_DECIMAL_TYPE_ADAPTER = new BigDecimalTypeAdapter();
@@ -88,7 +92,7 @@ final class DefaultTypeAdapters {
   private static final TreeSetCreator TREE_SET_CREATOR = new TreeSetCreator();
   private static final HashSetCreator HASH_SET_CREATOR = new HashSetCreator();
   private static final GregorianCalendarTypeAdapter GREGORIAN_CALENDAR_TYPE_ADAPTER =
-    new GregorianCalendarTypeAdapter();
+      new GregorianCalendarTypeAdapter();
 
   // The constants DEFAULT_SERIALIZERS, DEFAULT_DESERIALIZERS, and DEFAULT_INSTANCE_CREATORS
   // must be defined after the constants for the type adapters. Otherwise, the type adapter
@@ -105,6 +109,7 @@ final class DefaultTypeAdapters {
         new ParameterizedTypeHandlerMap<JsonSerializer<?>>();
 
     map.registerForTypeHierarchy(Enum.class, ENUM_TYPE_ADAPTER);
+    map.registerForTypeHierarchy(InetAddress.class, INET_ADDRESS_ADAPTER);
     map.register(URL.class, URL_TYPE_ADAPTER);
     map.register(URI.class, URI_TYPE_ADAPTER);
     map.register(UUID.class, UUUID_TYPE_ADAPTER);
@@ -142,6 +147,7 @@ final class DefaultTypeAdapters {
     ParameterizedTypeHandlerMap<JsonDeserializer<?>> map =
         new ParameterizedTypeHandlerMap<JsonDeserializer<?>>();
     map.registerForTypeHierarchy(Enum.class, wrapDeserializer(ENUM_TYPE_ADAPTER));
+    map.registerForTypeHierarchy(InetAddress.class, wrapDeserializer(INET_ADDRESS_ADAPTER));
     map.register(URL.class, wrapDeserializer(URL_TYPE_ADAPTER));
     map.register(URI.class, wrapDeserializer(URI_TYPE_ADAPTER));
     map.register(UUID.class, wrapDeserializer(UUUID_TYPE_ADAPTER));
@@ -397,6 +403,24 @@ final class DefaultTypeAdapters {
     }
   }
 
+  static class DefaultInetAddressAdapter
+      implements JsonDeserializer<InetAddress>, JsonSerializer<InetAddress> {
+
+    public InetAddress deserialize(JsonElement json, Type typeOfT,
+        JsonDeserializationContext context) throws JsonParseException {
+      try {
+        return InetAddress.getByName(json.getAsString());
+      } catch (UnknownHostException e) {
+        throw new JsonParseException(e);
+      }
+    }
+    
+    public JsonElement serialize(InetAddress src, Type typeOfSrc,
+        JsonSerializationContext context) {
+      return new JsonPrimitive(src.getHostAddress());
+    }
+  }
+
   @SuppressWarnings("unchecked")
   private static class EnumTypeAdapter<T extends Enum<T>>
       implements JsonSerializer<T>, JsonDeserializer<T> {

gson/src/test/java/com/google/gson/DefaultInetAddressTypeAdapterTest.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2011 Google Inc.
+ *
+ * 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.google.gson;
+
+import java.net.InetAddress;
+
+import junit.framework.TestCase;
+
+/**
+ * Unit tests for the default serializer/deserializer for the {@code InetAddress} type.
+ * 
+ * @author Joel Leitch
+ */
+public class DefaultInetAddressTypeAdapterTest extends TestCase {
+  private Gson gson;
+  
+  @Override
+  protected void setUp() throws Exception {
+    super.setUp();
+    gson = new Gson();
+  }
+  
+  public void testInetAddressSerializationAndDeserialization() throws Exception {
+    InetAddress localhost = InetAddress.getLocalHost();
+    String localInetAddress = gson.toJson(localhost);
+    assertEquals("\"" + localhost.getHostAddress() + "\"", localInetAddress);
+    
+    InetAddress value = gson.fromJson(localInetAddress, InetAddress.class);
+    assertEquals(localhost, value);
+  } 
+}