| /** |
| * 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.hadoop.streaming; |
| |
| import java.io.DataInputStream; |
| import java.io.EOFException; |
| import java.io.IOException; |
| |
| import org.apache.hadoop.io.IntWritable; |
| |
| public class RawBytesReduceApp { |
| private DataInputStream dis; |
| |
| public RawBytesReduceApp() { |
| dis = new DataInputStream(System.in); |
| } |
| |
| public void go() throws IOException { |
| String prevKey = null; |
| int sum = 0; |
| String key = readString(); |
| while (key != null) { |
| if (prevKey != null && !key.equals(prevKey)) { |
| System.out.println(prevKey + "\t" + sum); |
| sum = 0; |
| } |
| sum += readInt(); |
| prevKey = key; |
| key = readString(); |
| } |
| System.out.println(prevKey + "\t" + sum); |
| System.out.flush(); |
| } |
| |
| public static void main(String[] args) throws IOException { |
| RawBytesReduceApp app = new RawBytesReduceApp(); |
| app.go(); |
| } |
| |
| private String readString() throws IOException { |
| int length; |
| try { |
| length = dis.readInt(); |
| } catch (EOFException eof) { |
| return null; |
| } |
| byte[] bytes = new byte[length]; |
| dis.readFully(bytes); |
| return new String(bytes, "UTF-8"); |
| } |
| |
| private int readInt() throws IOException { |
| dis.readInt(); // ignore (we know it's 4) |
| IntWritable iw = new IntWritable(); |
| iw.readFields(dis); |
| return iw.get(); |
| } |
| } |