在Java中使用notify时，线程和可运行之间有什么区别吗？

当我尝试对Java中的notify（）进行测试时，发现有些困惑。

在这里，我有两个线程b1和b2，它们具有对另一个线程a的引用。在b1和b2中，它们将调用wait（）。在线程a中，它将调用notify（）。据我所知，它将调用b1或b2重新开始。当我使用Runnable实现这一点时，确实如此。但是当我使用Thread意识到这一点时，b1和b2都重新开始。有人可以解释吗？

这是代码。

使用Runnable实现：

线程A：

public class threada implements Runnable{

    @Override
    public void run() {
        // TODO Auto-generated method stub
        String name = Thread.currentThread().getName();
        System.out.println(name+" started");
        synchronized(this){
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            System.out.println(name + "end");
            notify();
        }
    }
}

线程B：

public class threadb implements Runnable{

    private threada ta;
    public threadb(threada a){
        ta = a;
    }

    @Override
    public void run() {
        // TODO Auto-generated method stub
        String name = Thread.currentThread().getName();
        System.out.println(name + " started");
        synchronized(ta){
            try {
                ta.wait();
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            System.out.println(name + "end");
        }
    }

}

主要：

public class threadmain {
    public static void main(String...args){
        threada a = new threada();

        threadb b1 = new threadb(a);
        threadb b2 = new threadb(a);

        new Thread(b1, "b1").start();
        new Thread(b2, "b2").start();

        new Thread(a, "a").start();
    }
}

结果：

b1 started
a started
b2 started
aend
b1end

使用线程实现：

线程A：

public class ThreadA extends Thread{

    @Override
    public void run() {
        String name = Thread.currentThread().getName();
        System.out.println(name+" started");
        synchronized(this){
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            System.out.println(name + "end");
            notify();
        }
    }
}

线程B：

public class ThreadB extends Thread{

    private ThreadA ta;
    public ThreadB(ThreadA a){
        ta = a;
    }
    @Override
    public void run() {
        // TODO Auto-generated method stub
//      super.run();
        String name = Thread.currentThread().getName();
        System.out.println(name + " started");
        synchronized(ta){
            try {
                ta.wait();
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            System.out.println(name + "end");
        }
    }
}

主要：

public class ThreadMain {
    public static void main(String... args) throws InterruptedException {
        ThreadA a = new ThreadA();

        ThreadB b1 = new ThreadB(a);
        ThreadB b2 = new ThreadB(a);
        b1.setName("b1");
        b2.setName("b2");

        b1.start();
        b2.start();

        Thread.sleep(10);

        a.setName("a");
        a.start();
    }
}

结果：

b1 started
b2 started
a started
aend
b1end
b2end