MyWritable.java

public class MyWritable implements Writable {
  // Some data    
  private int counter;
  private long timestamp;
      
  public void write(DataOutput out) throws IOException {
    out.writeInt(counter);
    out.writeLong(timestamp);
  }
      
  public void readFields(DataInput in) throws IOException {
    counter = in.readInt();
    timestamp = in.readLong();
  }
      
  public static MyWritable read(DataInput in) throws IOException {
    MyWritable w = new MyWritable();
    w.readFields(in);
    return w;
  }
}