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@@ -0,0 +1,62 @@
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+package me.yoqi.hadoop.test;
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+import java.io.IOException;
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+import java.util.StringTokenizer;
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+
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+import org.apache.hadoop.conf.Configuration;
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+import org.apache.hadoop.fs.Path;
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+import org.apache.hadoop.io.IntWritable;
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+import org.apache.hadoop.io.Text;
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+import org.apache.hadoop.mapreduce.Job;
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+import org.apache.hadoop.mapreduce.Mapper;
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+import org.apache.hadoop.mapreduce.Reducer;
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+import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
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+import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
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+
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+public class WordCount {
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+
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+ public static class TokenizerMapper
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+ extends Mapper<Object, Text, Text, IntWritable>{
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+
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+ private final static IntWritable one = new IntWritable(1);
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+ private Text word = new Text();
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+
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+ public void map(Object key, Text value, Context context
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+ ) throws IOException, InterruptedException {
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+ StringTokenizer itr = new StringTokenizer(value.toString());
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+ while (itr.hasMoreTokens()) {
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+ word.set(itr.nextToken());
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+ context.write(word, one);
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+ }
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+ }
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+ }
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+
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+ public static class IntSumReducer
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+ extends Reducer<Text,IntWritable,Text,IntWritable> {
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+ private IntWritable result = new IntWritable();
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+
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+ public void reduce(Text key, Iterable<IntWritable> values,
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+ Context context
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+ ) throws IOException, InterruptedException {
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+ int sum = 0;
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+ for (IntWritable val : values) {
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+ sum += val.get();
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+ }
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+ result.set(sum);
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+ context.write(key, result);
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+ }
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+ }
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+
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+ public static void main(String[] args) throws Exception {
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+ Configuration conf = new Configuration();
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+ Job job = Job.getInstance(conf, "word count");
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+ job.setJarByClass(WordCount.class);
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+ job.setMapperClass(TokenizerMapper.class);
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+ job.setCombinerClass(IntSumReducer.class);
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+ job.setReducerClass(IntSumReducer.class);
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+ job.setOutputKeyClass(Text.class);
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+ job.setOutputValueClass(IntWritable.class);
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+ FileInputFormat.addInputPath(job, new Path(args[0]));
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+ FileOutputFormat.setOutputPath(job, new Path(args[1]));
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+ System.exit(job.waitForCompletion(true) ? 0 : 1);
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+ }
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+}
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