class Run1 implements Runnable {
  String s;
  boolean wait = true;
  Run1(String s) {
    this.s = s;
  }
  public synchronized void run() {
    System.out.println("run " + s);
    try {
      Thread.sleep(4000);
    } catch (InterruptedException ex) {
    }
    wait = false;
    System.out.println("notify for run " + s);
    notifyAll();
  }
  public synchronized void get() {
    while (true) {
      try {
        System.out.println("wait...");
        wait();
        if (!(wait)) break;
        System.out.println("recv notify...");
      } catch (InterruptedException ex) {
      }
    }
  }
}


public class TestThread {

  public synchronized void testIt() throws Exception {
    Run1 run1 = new Run1("1");
    Run1 run2 = new Run1("2");
    Thread t1 = new Thread(run1);
    t1.start();
    Thread t2 = new Thread(run2);
    t2.start();

    run1.get();
    run2.get();

  }

  public static void main(String[] args) throws Exception {
    TestThread t = new TestThread();
    t.testIt();
  }

}