hbase-common/src/main/java/org/apache/hadoop/hbase/util/GsonUtil.java

   1 /**
   2  * Licensed to the Apache Software Foundation (ASF) under one
   3  * or more contributor license agreements.  See the NOTICE file
   4  * distributed with this work for additional information
   5  * regarding copyright ownership.  The ASF licenses this file
   6  * to you under the Apache License, Version 2.0 (the
   7  * "License"); you may not use this file except in compliance
   8  * with the License.  You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  */
  18 package org.apache.hadoop.hbase.util;
  19
  20 import java.io.IOException;
  21 import java.util.concurrent.atomic.LongAdder;
  22 import org.apache.yetus.audience.InterfaceAudience;
  23
  24 import org.apache.hbase.thirdparty.com.google.gson.GsonBuilder;
  25 import org.apache.hbase.thirdparty.com.google.gson.LongSerializationPolicy;
  26 import org.apache.hbase.thirdparty.com.google.gson.TypeAdapter;
  27 import org.apache.hbase.thirdparty.com.google.gson.stream.JsonReader;
  28 import org.apache.hbase.thirdparty.com.google.gson.stream.JsonWriter;
  29
  30 /**
  31  * Helper class for gson.
  32  */
  33 @InterfaceAudience.Private
  34 public final class GsonUtil {
  35
  36   private GsonUtil() {
  37   }
  38
  39   /**
  40    * Create a builder which is used to create a Gson instance.
  41    * <p/>
  42    * Will set some common configs for the builder.
  43    */
  44   public static GsonBuilder createGson() {
  45     return new GsonBuilder().setLongSerializationPolicy(LongSerializationPolicy.STRING)
  46       .registerTypeAdapter(LongAdder.class, new TypeAdapter<LongAdder>() {
  47
  48         @Override
  49         public void write(JsonWriter out, LongAdder value) throws IOException {
  50           out.value(value.longValue());
  51         }
  52
  53         @Override
  54         public LongAdder read(JsonReader in) throws IOException {
  55           LongAdder value = new LongAdder();
  56           value.add(in.nextLong());
  57           return value;
  58         }
  59       });
  60   }
  61 }