/**
* 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.tajo.json;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import org.apache.tajo.datum.Datum;
import org.apache.tajo.util.TUtil;
import java.lang.reflect.Type;
import java.util.Map;
public class CommonGsonHelper {
private static Gson gson;
private static Gson gsonPretty;
private CommonGsonHelper() {
}
private static Map<Type, GsonSerDerAdapter> registerAdapters() {
Map<Type, GsonSerDerAdapter> adapters = TUtil.newHashMap();
adapters.put(Datum.class, new DatumAdapter());
return adapters;
}
public static Gson getInstance() {
if (gson == null ) {
GsonHelper helper = new GsonHelper(registerAdapters());
gson = helper.getGson();
}
return gson;
}
public static Gson getPrettyInstance() {
if (gsonPretty == null) {
GsonBuilder prettyBuilder = new GsonBuilder()
.setPrettyPrinting()
.excludeFieldsWithoutExposeAnnotation();
GsonHelper.registerAdapters(prettyBuilder, registerAdapters());
gsonPretty = prettyBuilder.create();
}
return gsonPretty;
}
public static String toJson(GsonObject object, Class<? extends GsonObject> clazz) {
return getInstance().toJson(object, clazz);
}
public static <T extends GsonObject> T fromJson(String json, Class<T> clazz) {
return getInstance().fromJson(json, clazz);
}
}