多线程1

1.

public class MyThread extends Thread{
    private  int count = 5;
    
    @Override
    public synchronized void run() {
        count--;
        System.out.println(Thread.currentThread().getName() + ":count="+count);
    }

    public static void main(String[] args) {
        /*MyThread t1 = new MyThread();
        MyThread t2 = new MyThread();
        MyThread t3= new MyThread();
        MyThread t4 = new MyThread();
        MyThread t5 = new MyThread();
        t1.start();
        t2.start();
        t3.start();
        t4.start();
        t5.start();
        结果:
                Thread-4:count=4
                Thread-1:count=4
                Thread-2:count=4
                Thread-3:count=4
                Thread-5:count=4 */
        
        MyThread myThread = new MyThread();
        Thread t1 = new Thread(myThread, "t1");
        Thread t2 = new Thread(myThread, "t2");
        Thread t3 = new Thread(myThread, "t3");
        Thread t4 = new Thread(myThread, "t4");
        Thread t5 = new Thread(myThread, "t5");
        t1.start();
        t2.start();
        t3.start();
        t4.start();
        t5.start();
        /*
            t1:count=4
            t4:count=3
            t2:count=2
            t3:count=1
            t5:count=0    
         */
    }
}