[120] | 1 | /** |
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| 2 | * Licensed to the Apache Software Foundation (ASF) under one |
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| 3 | * or more contributor license agreements. See the NOTICE file |
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| 4 | * distributed with this work for additional information |
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| 5 | * regarding copyright ownership. The ASF licenses this file |
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| 6 | * to you under the Apache License, Version 2.0 (the |
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| 7 | * "License"); you may not use this file except in compliance |
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| 8 | * with the License. You may obtain a copy of the License at |
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| 9 | * |
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| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
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| 11 | * |
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| 12 | * Unless required by applicable law or agreed to in writing, software |
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| 13 | * distributed under the License is distributed on an "AS IS" BASIS, |
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| 14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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| 15 | * See the License for the specific language governing permissions and |
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| 16 | * limitations under the License. |
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| 17 | */ |
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| 18 | |
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| 19 | package testjar; |
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| 20 | |
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| 21 | import java.io.IOException; |
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| 22 | import java.util.Iterator; |
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| 23 | |
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| 24 | import org.apache.hadoop.io.IntWritable; |
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| 25 | import org.apache.hadoop.io.Text; |
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| 26 | import org.apache.hadoop.io.Writable; |
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| 27 | import org.apache.hadoop.io.WritableComparable; |
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| 28 | import org.apache.hadoop.mapred.JobConf; |
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| 29 | import org.apache.hadoop.mapred.Mapper; |
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| 30 | import org.apache.hadoop.mapred.OutputCollector; |
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| 31 | import org.apache.hadoop.mapred.Reducer; |
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| 32 | import org.apache.hadoop.mapred.Reporter; |
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| 33 | |
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| 34 | public class ExternalMapperReducer |
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| 35 | implements Mapper<WritableComparable, Writable, |
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| 36 | ExternalWritable, IntWritable>, |
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| 37 | Reducer<WritableComparable, Writable, |
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| 38 | WritableComparable, IntWritable> { |
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| 39 | |
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| 40 | public void configure(JobConf job) { |
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| 41 | |
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| 42 | } |
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| 43 | |
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| 44 | public void close() |
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| 45 | throws IOException { |
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| 46 | |
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| 47 | } |
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| 48 | |
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| 49 | public void map(WritableComparable key, Writable value, |
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| 50 | OutputCollector<ExternalWritable, IntWritable> output, |
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| 51 | Reporter reporter) |
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| 52 | throws IOException { |
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| 53 | |
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| 54 | if (value instanceof Text) { |
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| 55 | Text text = (Text)value; |
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| 56 | ExternalWritable ext = new ExternalWritable(text.toString()); |
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| 57 | output.collect(ext, new IntWritable(1)); |
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| 58 | } |
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| 59 | } |
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| 60 | |
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| 61 | public void reduce(WritableComparable key, Iterator<Writable> values, |
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| 62 | OutputCollector<WritableComparable, IntWritable> output, |
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| 63 | Reporter reporter) |
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| 64 | throws IOException { |
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| 65 | |
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| 66 | int count = 0; |
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| 67 | while (values.hasNext()) { |
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| 68 | count++; |
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| 69 | values.next(); |
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| 70 | } |
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| 71 | output.collect(key, new IntWritable(count)); |
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| 72 | } |
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| 73 | } |
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