synchronized锁对象

1：定义线程，oneThread

public class OneThread implements Runnable {

    @Override
    public void run() {
        synchronized (this){
            for (int i =0;i< 100;i++){
                System.out.println(Thread.currentThread().getName()+"开始的编程号码为"+i);
                if (i == 10){
                    Thread.yield();
                }
            }
        }
    }
}

2：开始调用线程

public class TestThread {

    public static void main(String[] args) {
        Thread oneThread = new Thread(new OneThread(),"线程ONE");

        Thread twoThread = new Thread(new OneThread(),"线程TWO");

        oneThread.start();
        twoThread.start();
    }
}

如此使用，synchronized锁会失效，因为new的是两个对象，synchronized获取的是两把不同的锁，所以会导致并发失效

3：修改synchronized是并发访问有效

public class OneThread implements Runnable {
    @Override
    public void run() {
        synchronized (OneThread.class){
            for (int i =0;i< 100;i++){
                System.out.println(Thread.currentThread().getName()+"开始的编程号码为"+i);
                if (i == 10){
                    Thread.yield();
                }
            }
        }
    }
}