读写锁 与 信号锁 的使用方法

读写锁

在类 中new一个读写锁对象

private ReadWriteLock readWriteLock=new ReentrantReadWriteLock();

在需要加读锁的代码段之前加入

readWriteLock.readLock().lock();

代码段之后加入

readWriteLock.readLock().unlock();

整体效果

 public SubscribeOrderVO queryOrder(OrderInfoReq orderInfoReq) throws ParseException, InterruptedException {
     readWriteLock.readLock().lock();
     Customer customer = customerMapper.queryByPhone(orderInfoReq.getCustomerPhone());
     readWriteLock.readLock().unlock();
}

信号锁

类中建立对象

 private Semaphore semaphore=new Semaphore(1);

代码段之前

semaphore.acquire();

代码段之后

semaphore.release();