使用AtomicInteger写一个显示锁

利用了AtomicInteger的compareAndSet方法

public class CASLock {
 
    private  AtomicInteger value = new AtomicInteger();
 
    Thread  lockThread ;
 
    public boolean tryLock() {
        if(value.compareAndSet(, )) {
            lockThread = Thread.currentThread();
            return true;
        }else {
            return false;
        }
    }
 
    public void unLock() {
        if(value.get() == ) {
            return;
        }
        if(lockThread == Thread.currentThread()) {
            value.compareAndSet(, );
        }
    }
}
 
public class CASLockTest {
 
    static CASLock lock = new CASLock();
 
    public static void main(String[] args) {
 
        IntStream.rangeClosed(, ).forEach(x -> {
            new Thread() {
                public void run() {
                    doSomething();
                }
            }.start();
        });
    }
 
    public static void doSomething() {
        try {
            if (lock.tryLock()) {
                System.out.println(Thread.currentThread().getName() + " get the lock ");
                try {
                    Thread.sleep();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            } else {
                System.out.println(Thread.currentThread().getName() + " can not get the lock ");
            }
        } finally {
            lock.unLock();
        }
 
    }
}