多线程 -- 锁 lock

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锁 lock

 

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相关接口

 

public interface Lock {

    void lock();   //加锁

    void lockInterruptibly() throws InterruptedException;
                   //加锁，锁可响应中断

    boolean tryLock();
                   //立即获取锁，若不能获得锁，返回false

    boolean tryLock(long time, TimeUnit unit) throws InterruptedException;
                   //在指定时间获取锁，若不能获得锁返回false

    void unlock();
                   //释放锁

    Condition newCondition();
                  //生成Condition对象

}

 

接口实现类

ReentrantLock：锁可重入，同一线程可多次获得相同的锁

ReentrantReadWriteLock：读写锁，可实现锁分离，读读不冲突，读写、写写冲突

StampedLock：可实现乐观读，读写不冲突

 

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使用示例：

 

class Thread7 implements Runnable{

    private ReentrantLock lock=new ReentrantLock();

    @Override
    public void run() {
        try{
            lock.lock();
            System.out.println("获得lock锁"+" "+Thread.currentThread().getId());
            Thread.sleep(1000);

        }catch (Exception e){
            e.printStackTrace();
        }finally {
            System.out.println("释放lock锁:"+" "+Thread.currentThread().getId());
            lock.unlock();
        }
    }
}

public class ThreadTest7 {

    public static void main(String[] args){
        Thread7 t=new Thread7();
        Thread t1=new Thread(t);
        Thread t2=new Thread(t);
        t1.start();
        t2.start();
    }
}

 

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控制台输出：

 

获得lock锁 15
释放lock锁: 15
获得lock锁 14
释放lock锁: 14