public static void main(String[] args) throws Exception {
		Configuration conf = new Configuration();
        String[] otherArgs  = new GenericOptionsParser(conf, args).getRemainingArgs();
        if (otherArgs.length != 4){
            System.err.println("Usage: <int> <out> <clusterIDMap> <k>");
            System.exit(2);
        }
        conf.set("clusterIDMappath", otherArgs[2]);
        conf.set("kpath", otherArgs[3]);
        Job job = new Job(conf, "SimItemJob");
        job.setJarByClass(SimItemDriver.class);

        Path in = new Path(otherArgs[0]);
        Path out = new Path(otherArgs[1]);
        FileInputFormat.addInputPath(job, in);
        FileSystem fs = FileSystem.get(conf);
        if (fs.exists(out)){
            fs.delete(out, true);
        }
        FileOutputFormat.setOutputPath(job, out);

        job.setMapperClass(SimItemMapper.class);
        job.setReducerClass(SimItemReducer.class);//设置Reduce类

        job.setOutputKeyClass(IntWritable.class);
        job.setOutputValueClass(Text.class);

        job.waitForCompletion(true);
	}