void checkFormat(Job job) throws Exception {
    TaskAttemptContext attemptContext =
        new TaskAttemptContext(job.getConfiguration(), new TaskAttemptID("123", 0, false, 1, 2));

    MyClassMessagePackBase64LineInputFormat format = new MyClassMessagePackBase64LineInputFormat();
    FileInputFormat.setInputPaths(job, workDir);

    List<InputSplit> splits = format.getSplits(job);
    for (int j = 0; j < splits.size(); j++) {
      RecordReader<LongWritable, MyClassWritable> reader =
          format.createRecordReader(splits.get(j), attemptContext);
      reader.initialize(splits.get(j), attemptContext);

      int count = 0;
      try {
        while (reader.nextKeyValue()) {
          LongWritable key = reader.getCurrentKey();
          MyClassWritable val = reader.getCurrentValue();
          MyClass mc = val.get();
          assertEquals(mc.v, count);
          assertEquals(mc.s, Integer.toString(count));
          count++;
        }
      } finally {
        reader.close();
      }
    }
  }
 public K getCurrentKey() throws IOException, InterruptedException {
   return curReader.getCurrentKey();
 }
 @Override
 public K getCurrentKey() throws IOException, InterruptedException {
   return originalRR.getCurrentKey();
 }