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 | |
---|
19 | #include "hadoop/Pipes.hh" |
---|
20 | #include "hadoop/TemplateFactory.hh" |
---|
21 | #include "hadoop/StringUtils.hh" |
---|
22 | |
---|
23 | const std::string WORDCOUNT = "WORDCOUNT"; |
---|
24 | const std::string INPUT_WORDS = "INPUT_WORDS"; |
---|
25 | const std::string OUTPUT_WORDS = "OUTPUT_WORDS"; |
---|
26 | |
---|
27 | class WordCountMap: public HadoopPipes::Mapper { |
---|
28 | public: |
---|
29 | HadoopPipes::TaskContext::Counter* inputWords; |
---|
30 | |
---|
31 | WordCountMap(HadoopPipes::TaskContext& context) { |
---|
32 | inputWords = context.getCounter(WORDCOUNT, INPUT_WORDS); |
---|
33 | } |
---|
34 | |
---|
35 | void map(HadoopPipes::MapContext& context) { |
---|
36 | std::vector<std::string> words = |
---|
37 | HadoopUtils::splitString(context.getInputValue(), " "); |
---|
38 | for(unsigned int i=0; i < words.size(); ++i) { |
---|
39 | context.emit(words[i], "1"); |
---|
40 | } |
---|
41 | context.incrementCounter(inputWords, words.size()); |
---|
42 | } |
---|
43 | }; |
---|
44 | |
---|
45 | class WordCountReduce: public HadoopPipes::Reducer { |
---|
46 | public: |
---|
47 | HadoopPipes::TaskContext::Counter* outputWords; |
---|
48 | |
---|
49 | WordCountReduce(HadoopPipes::TaskContext& context) { |
---|
50 | outputWords = context.getCounter(WORDCOUNT, OUTPUT_WORDS); |
---|
51 | } |
---|
52 | |
---|
53 | void reduce(HadoopPipes::ReduceContext& context) { |
---|
54 | int sum = 0; |
---|
55 | while (context.nextValue()) { |
---|
56 | sum += HadoopUtils::toInt(context.getInputValue()); |
---|
57 | } |
---|
58 | context.emit(context.getInputKey(), HadoopUtils::toString(sum)); |
---|
59 | context.incrementCounter(outputWords, 1); |
---|
60 | } |
---|
61 | }; |
---|
62 | |
---|
63 | class WordCountPartitioner: public HadoopPipes::Partitioner { |
---|
64 | public: |
---|
65 | WordCountPartitioner(HadoopPipes::TaskContext& context){} |
---|
66 | virtual int partition(const std::string& key, int numOfReduces) { |
---|
67 | return 0; |
---|
68 | } |
---|
69 | }; |
---|
70 | |
---|
71 | int main(int argc, char *argv[]) { |
---|
72 | return HadoopPipes::runTask(HadoopPipes::TemplateFactory<WordCountMap, |
---|
73 | WordCountReduce,WordCountPartitioner, |
---|
74 | WordCountReduce>()); |
---|
75 | } |
---|
76 | |
---|