package test;import java.io.IOException;import java.util.StringTokenizer;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.fs.Path;import org.apache.hadoop.io.IntWritable;import org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.Job;import org.apache.hadoop.mapreduce.Mapper;import org.apache.hadoop.mapreduce.Reducer;import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;import org.apache.hadoop.util.GenericOptionsParser; public class WordCount {   public static class TokenizerMapper       extends Mapper
     
      {         private final static IntWritable one = new IntWritable(1);    private Text word = new Text();           public void map(Object key, Text value, Context context                    ) throws IOException, InterruptedException {      StringTokenizer itr = new StringTokenizer(value.toString());      while (itr.hasMoreTokens()) {        word.set(itr.nextToken());        context.write(word, one);      }    }  }     public static class IntSumReducer extends Reducer
      
        {    private IntWritable result = new IntWritable();                public void reduce(Text key, Iterable
       
         values,                       Context context                       ) throws IOException, InterruptedException {      int sum = 0;      for (IntWritable val : values) {        sum += val.get();      }      result.set(sum);      context.write(key, result);    }          }   public static void main(String[] args) throws Exception {    Configuration conf = new Configuration();    //conf.set("mapred.job.tracker", "192.168.2.35:9001");  //在你的文件地址前自动添加：hdfs://master:9000/    //conf.set("fs.defaultFS", "hdfs://192.168.2.35:9001/");    //conf.set("hadoop.job.user","hadoop");      //指定jobtracker的ip和端口号，master在/etc/hosts中可以配置    //conf.set("mapred.job.tracker","192.168.2.35:9001");        //在你的文件地址前自动添加：hdfs://master:9000/    conf.set("fs.defaultFS", "hdfs://192.168.2.35:9000/");    conf.set("hadoop.job.user","hadoop");      conf.set("Master","1234");    //指定jobtracker的ip和端口号，master在/etc/hosts中可以配置    //conf.set("mapred.job.tracker","Master:9001");    String[] ars=new String[]{"input","out"};    String[] otherArgs = new GenericOptionsParser(conf, ars).getRemainingArgs();    if (otherArgs.length != 2) {      System.err.println("Usage: wordcount  ");      System.exit(2);    }    Job job = new Job(conf, "wordcount");    job.setJarByClass(WordCount.class);    job.setMapperClass(TokenizerMapper.class);    job.setCombinerClass(IntSumReducer.class);    job.setReducerClass(IntSumReducer.class);    job.setOutputKeyClass(Text.class);    job.setOutputValueClass(IntWritable.class);    FileInputFormat.addInputPath(job, new Path(otherArgs[0]));    FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));    System.exit(job.waitForCompletion(true) ? 0 : 1);  }}