content: package hip.ch3.json;
  
  
  import hip.util.Cli;
  import hip.util.CliCommonOpts;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.conf.Configured;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.io.LongWritable;
  import org.apache.hadoop.io.MapWritable;
  import org.apache.hadoop.io.Text;
  import org.apache.hadoop.io.Writable;
  import org.apache.hadoop.mapreduce.Job;
  import org.apache.hadoop.mapreduce.Mapper;
  import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
  import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
  import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
  import org.apache.hadoop.util.Tool;
  import org.apache.hadoop.util.ToolRunner;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.IOException;
  
  public final class JsonMapReduce extends Configured implements Tool {
    private static final Logger log = LoggerFactory.getLogger
        (JsonMapReduce.class);
  
    public static class Map extends Mapper<LongWritable, MapWritable,
        Text, Text> {
  
      @Override
      protected void map(LongWritable key, MapWritable value,
                         Context context)
          throws
          IOException, InterruptedException {
  
        for (java.util.Map.Entry<Writable, Writable> entry : value
            .entrySet()) {
          context.write((Text) entry.getKey(), (Text) entry.getValue());
        }
      }
    }
  
    /**
     * Main entry point for the example.
     *
     * @param args arguments
     * @throws Exception when something goes wrong
     */
    public static void main(final String[] args) throws Exception {
      int res = ToolRunner.run(new Configuration(), new JsonMapReduce(), args);
      System.exit(res);
    }
  
    /**
     * The MapReduce driver - setup and launch the job.
     *
     * @param args the command-line arguments
     * @return the process exit code
     * @throws Exception if something goes wrong
     */
    public int run(final String[] args) throws Exception {
  
  
      Cli cli = Cli.builder().setArgs(args).addOptions(CliCommonOpts.MrIoOpts.values()).build();
      int result = cli.runCmd();
  
      if (result != 0) {
        return result;
      }
  
      Path inputPath = new Path(cli.getArgValueAsString(CliCommonOpts.MrIoOpts.INPUT));
      Path outputPath = new Path(cli.getArgValueAsString(CliCommonOpts.MrIoOpts.OUTPUT));
  
      Configuration conf = super.getConf();
      Job job = new Job(conf);
      job.setJarByClass(JsonMapReduce.class);
      job.setOutputKeyClass(Text.class);
      job.setOutputValueClass(Text.class);
      job.setMapperClass(Map.class);
      job.setInputFormatClass(JsonInputFormat.class);
      job.setNumReduceTasks(0);
      job.setOutputFormatClass(TextOutputFormat.class);
  
      FileInputFormat.setInputPaths(job, inputPath);
      FileOutputFormat.setOutputPath(job, outputPath);
  
      if (job.waitForCompletion(true)) {
        return 0;
      }
      return 1;
    }
  }
  