| /** |
| * 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.algebra; |
| |
| import com.google.gson.Gson; |
| import com.google.gson.GsonBuilder; |
| import org.apache.tajo.algebra.CreateTable.PartitionMethodDescExpr; |
| |
| public class JsonHelper { |
| private static JsonHelper instance; |
| |
| private GsonBuilder builder; |
| private Gson gson; |
| |
| static { |
| instance = new JsonHelper(); |
| } |
| |
| private JsonHelper() { |
| initBuilder(); |
| gson = builder.create(); |
| } |
| |
| private void initBuilder() { |
| builder = new GsonBuilder().setPrettyPrinting(). |
| excludeFieldsWithoutExposeAnnotation(); |
| builder.registerTypeAdapter(OpType.class, new OpType.JsonSerDer()); |
| builder.registerTypeAdapter(Expr.class, new Expr.JsonSerDer()); |
| builder.registerTypeAdapter(PartitionMethodDescExpr.class, new PartitionMethodDescExpr.JsonSerDer()); |
| } |
| |
| |
| public static Gson getInstance() { |
| return instance.gson; |
| } |
| |
| public static String toJson(Object obj) { |
| return instance.gson.toJson(obj); |
| } |
| |
| public static <T> T fromJson(String json, Class<T> clazz) { |
| return instance.gson.fromJson(json, clazz); |
| } |
| } |