Hadoop基本的Map/Reduce

HelloHadoop.class

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Mapper

public static void main(String[] args) {    Configuration conf = new Configuration();    Job job = new Job(conf, "Hadoop Hello World");    job.setJarByClass(HelloHadoop.class);    FileInputFormat.setInputPaths(job, "input");    FileOutputFormat.setOutputPath(job, new Path("output"));    job.setMapperClass(HelloMapper.class);    job.setReducerClass(HelloReducer.class);    job.waitForCompletion(true);}