code: public static SequenceFile.Reader[] getReaders(Configuration conf, Path dir)
      throws IOException {
      FileSystem fs = dir.getFileSystem(conf);
      Path[] names = FileUtil.stat2Paths(fs.listStatus(dir));
      
      // sort names, so that hash partitioning works
      Arrays.sort(names);
      
      SequenceFile.Reader[] parts = new SequenceFile.Reader[names.length];
      for (int i = 0; i < names.length; i++) {
        parts[i] = new SequenceFile.Reader(fs, names[i], conf);
      }
      return parts;
    }
docs: Open the output generated by this format.