public class Messager implements Runnable {  public static void main(String[] args) {   new Thread(new Messager("Wallace")).start();   new Thread(new Messager("Gromit")).start();  }  private String name;  public Messager(String name) { this.name = name; }  public void run() {   message(1); message(2);  }  private synchronized void message(int n) {   System.out.print(name + "-" + n + " ");  }}