mac上eclipse上運行word count

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1.開啟eclipse之後，建立wordcount項目

package wordcount;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.LongWritable;  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;  public class WordCount {      public static class TokenizerMapper extends Mapper<LongWritable, Text, Text, IntWritable>{          private final static IntWritable one = new IntWritable(1);          private Text word = new Text();          public void map(LongWritable 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<Text, IntWritable, Text, IntWritable> {          private IntWritable result = new IntWritable();          public void reduce(Text key, Iterable<IntWritable> 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();          if (args.length != 2) {              System.err.println("Usage: wordcount  ");              System.exit(2);          }          Job job = new Job(conf, "word count");          job.setJarByClass(WordCount.class);          job.setMapperClass(TokenizerMapper.class);          job.setReducerClass(IntSumReducer.class);          job.setMapOutputKeyClass(Text.class);          job.setMapOutputValueClass(IntWritable.class);          job.setOutputKeyClass(Text.class);          job.setOutputValueClass(IntWritable.class);          FileInputFormat.addInputPath(job, new Path(args[0]));          FileOutputFormat.setOutputPath(job, new Path(args[1]));          System.exit(job.waitForCompletion(true) ? 0 : 1);      }  }  

2.配置hadoop路徑。

把需要啟動並執行檔案放進input檔案夾，如何在eclipse上的run configuration上配置需要啟動並執行檔案路徑和運行結果路徑，中間用一個空格隔開，如何點擊apply-run,開始跑。

 

3.用終端查看結果

JIAS-MacBook-Pro:output jia$ cat part-r-00000 do    2excuse    1fine    1hello    2how    1me    1thank    2you    3