Java tutorial
/*********************************************************************************************************************** * Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu) * * 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 eu.stratosphere.hadoopcompatibility.mapreduce.wrapper; import java.io.DataInput; import java.io.DataOutput; import java.io.IOException; import org.apache.hadoop.io.Writable; import org.apache.hadoop.io.WritableFactories; import org.apache.hadoop.mapreduce.JobContext; import eu.stratosphere.core.io.InputSplit; public class HadoopInputSplit implements InputSplit { public transient org.apache.hadoop.mapreduce.InputSplit mapreduceInputSplit; public transient JobContext jobContext; private int splitNumber; public org.apache.hadoop.mapreduce.InputSplit getHadoopInputSplit() { return mapreduceInputSplit; } public HadoopInputSplit() { super(); } public HadoopInputSplit(org.apache.hadoop.mapreduce.InputSplit mapreduceInputSplit, JobContext jobContext) { if (!(mapreduceInputSplit instanceof Writable)) { throw new IllegalArgumentException("InputSplit must implement Writable interface."); } this.mapreduceInputSplit = mapreduceInputSplit; this.jobContext = jobContext; } @Override public void write(DataOutput out) throws IOException { out.writeInt(this.splitNumber); out.writeUTF(this.mapreduceInputSplit.getClass().getName()); Writable w = (Writable) this.mapreduceInputSplit; w.write(out); } @Override public void read(DataInput in) throws IOException { this.splitNumber = in.readInt(); String className = in.readUTF(); if (this.mapreduceInputSplit == null) { try { Class<? extends org.apache.hadoop.io.Writable> inputSplit = Class.forName(className) .asSubclass(org.apache.hadoop.io.Writable.class); this.mapreduceInputSplit = (org.apache.hadoop.mapreduce.InputSplit) WritableFactories .newInstance(inputSplit); } catch (Exception e) { throw new RuntimeException("Unable to create InputSplit", e); } } ((Writable) this.mapreduceInputSplit).readFields(in); } @Override public int getSplitNumber() { return this.splitNumber; } public void setSplitNumber(int splitNumber) { this.splitNumber = splitNumber; } }