| /** |
| * 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.avro.mapred.tether; |
| |
| import java.io.IOException; |
| import java.util.StringTokenizer; |
| |
| import org.apache.avro.mapred.Pair; |
| import org.apache.avro.util.Utf8; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** Example Java tethered mapreduce executable. Implements map and reduce |
| * functions for word count. */ |
| public class WordCountTask |
| extends TetherTask<Utf8,Pair<Utf8,Long>,Pair<Utf8,Long>> { |
| |
| static final Logger LOG = LoggerFactory.getLogger(WordCountTask.class); |
| @Override public void map(Utf8 text, Collector<Pair<Utf8,Long>> collector) |
| throws IOException { |
| StringTokenizer tokens = new StringTokenizer(text.toString()); |
| while (tokens.hasMoreTokens()) |
| collector.collect(new Pair<Utf8,Long>(new Utf8(tokens.nextToken()),1L)); |
| } |
| |
| private long sum; |
| |
| @Override public void reduce(Pair<Utf8,Long> wc, |
| Collector<Pair<Utf8,Long>> c) { |
| sum += wc.value(); |
| } |
| |
| @Override public void reduceFlush(Pair<Utf8,Long> wc, Collector<Pair<Utf8,Long>> c) |
| throws IOException { |
| wc.value(sum); |
| c.collect(wc); |
| sum = 0; |
| } |
| |
| public static void main(String[] args) throws Exception { |
| new TetherTaskRunner(new WordCountTask()).join(); |
| LOG.info("WordCountTask finished"); |
| } |
| |
| } |