详解java线程及线程与进程的区别

publicclassThread02implementsRunnable {

  publicstaticvoidmain(String[] args) {

    Runnable r =newThread02();

    Thread t1 =newThread(r,"t1");

    /**

     *   Thread源码

     *   public Thread(Runnable target, String name) {

          init(null, target, name, 0);

             }

     */

    Thread t2 =newThread(r,"t2");

    t1.start();// 启动线程t1，处于就绪状态，等待cpu

    t2.start();// 启动线程t2，处于就绪状态，等待cpu

    t1.run();// 主线程main调用对象t1的run方法

  }

  publicvoidrun() {

    System.out.println("thread's name is "

        + Thread.currentThread().getName());

  }

}

publicclassThread03extendsThread {

  publicstaticvoidmain(String[] args) {

    Thread03 t1 =newThread03();  //不注意的情况下写成了Thread t1=new Thread()  注：Thread03此时就是一个线程了

    t1.start();

  }

  publicvoidrun() {

    System.out.println("thread's name is "

        + Thread.currentThread().getName());

  }

}

publicclassThread01 {

  publicstaticvoidmain(String[] args) {

    Thread thread=newThread();

    thread.start();//真正起作用 的是run()

    /**而Thread中的run

     * public void run() {

      if (target != null) {

        target.run();

      }

      }

      所以自己创建的线程要重写run方法，把要执行的内容放到run()中，所以要实现接口或继承进而产生子类

     */

    //创建线程的方式1 thread子类方式（继承）

    Thread thread1=newThread(){

      publicvoidrun() {

        while(true){

          try{

            Thread.sleep(500);//休息500毫秒

          }catch(InterruptedException e) {

            e.printStackTrace();

          }

          //Thread.currentThread()得到当前线程

          System.out.println("线程1的名字是 "+Thread.currentThread().getName());

        }

      }

    };

//    thread1.start(); //不写  线程无法启动

 //创建线程的方式2 runnable方式（实现） 推荐使用

    Thread thread2=newThread(newRunnable(){

      publicvoidrun() {

        while(true){

          try{

            Thread.sleep(300);

          }catch(InterruptedException e) {

            e.printStackTrace();

          }

          System.out.println("thread2'name is "+Thread.currentThread().getName());

        }

      }});

//    thread2.start();

    //执行的是thread

    newThread(newRunnable(){

      publicvoidrun() {

        System.out.println("runnable "+Thread.currentThread().getName());

      }}){

      publicvoidrun() {//子类中的run方法覆盖父类中的run方法，这样就不会执行runnable

        System.out.println("thread "+Thread.currentThread().getName());

      }

    }.start();

  }

  /***

   * 在单个cpu中执行多线程很有可能降低执行效率而不是提高 一个人在不同地方做同一件事情

   */

}