Java线程监听,意外退出线程后自动重启的实现方法

packagecn.std.test;

importjava.util.Observable;

importcn.std.util.DateUtil;

publicclassRunThreadextendsObservableimplements Runnable{

  // 此方法一经调用，立马可以通知观察者，在本例中是监听线程

  publicvoid doBusiness(){

    if(true){

      super.setChanged();

    }

    notifyObservers();

  }

  @Override

  publicvoid run() {

    intc =0;

    while(true){ //模拟线程运行一段时间之后退出

      System.out.println("Runing- "+c+" "+DateUtil.getStdDateTime());

      try{

        Thread.sleep(2000);

      }catch(InterruptedException e) {

        e.printStackTrace();

        doBusiness();

        break;

      }

      c++;

      //模拟抛出异常

      try{

        if(c==4){

          Stringstr =null;

          str.length();//此处将会抛出空指针异常

        }

      }catch(Exception e) {

        e.printStackTrace();

        doBusiness();//在抛出异常时调用，通知观察者，让其重启线程

        break;//异常抛出之后，一定要跳出循环，保证将线程送进地狱

      }

    } 

  }

  publicstaticvoidmain(String[] args) {

    RunThreadrun =newRunThread();

    Listener listen =newListener();

    un.addObserver(listen);

    newThread(run).start();

    //run.doBusiness();

  }

}

packagecn.std.test;

importjava.util.Observable;

importjava.util.Observer;

publicclassListenerimplementsObserver{

  @Override

  publicvoid update(Observable o, Object arg) {

    System.out.println("RunThread死机");

    RunThreadrun =newRunThread();

    run.addObserver(this);

    newThread(run).start();

    System.out.println("RunThread重启");

  }

}