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.giraph.writable.kryo.serializers; 19 20 import com.esotericsoftware.kryo.Kryo; 21 import com.esotericsoftware.kryo.io.Input; 22 import com.esotericsoftware.kryo.serializers.FieldSerializer; 23 import com.google.common.base.Preconditions; 24 25 /** 26 * Serializer used to deserialize data into object, instead of creating a new 27 * value readIntoObject needs to be set right before deserialization is called 28 * on it. 29 * 30 * @param <T> Object type 31 */ 32 public class ReusableFieldSerializer<T> extends FieldSerializer<T> { 33 /** Current object into which to deserialize */ 34 private T readIntoObject; 35 36 /** 37 * Creates new reusable field serializer for a given type. 38 * @param kryo HadoopKryo object 39 * @param type Type of object 40 */ 41 public ReusableFieldSerializer(Kryo kryo, Class type) { 42 super(kryo, type); 43 } 44 45 public void setReadIntoObject(T value) { 46 this.readIntoObject = value; 47 } 48 49 @Override 50 protected T create(Kryo kryo, Input input, Class<T> type) { 51 Preconditions.checkNotNull(readIntoObject); 52 Preconditions.checkState(readIntoObject.getClass().equals(type)); 53 T toReturn = readIntoObject; 54 readIntoObject = null; 55 return toReturn; 56 } 57 }