Java并发——Exchanger

ゝ一世哀愁。 2021-08-30 22:17 409阅读 0赞

### Exchanger ###

Exchanger的功能可以使2个线程之间传输数据,它比生产者/消费者模式使用的 wait/notify要更加方便。

exchange()阻塞的特性：

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NvbGRfX19wbGF5_size_16_color_FFFFFF_t_70]

exchange()传递数据：

public class ThreadA extends Thread{ 
        private Exchanger<String> exchanger;
    
        public ThreadA(Exchanger<String> exchanger) { 
            this.exchanger = exchanger;
        }
    
        @Override
        public void run() { 
            try { 
                System.out.println("在线程A中得到线程B的值=" + exchanger.exchange("A"));
            } catch (InterruptedException e) { 
                e.printStackTrace();
            }
        }
    }
    
    public class ThreadB extends Thread { 
        private Exchanger<String> exchanger;
    
        public ThreadB(Exchanger<String> exchanger) { 
            this.exchanger = exchanger;
        }
    
        @Override
        public void run() { 
            try { 
                System.out.println("在线程B中得到线程A的值=" + exchanger.exchange("B"));
            } catch (InterruptedException e) { 
                e.printStackTrace();
            }
        }
    
        public static void main(String[] args) { 
            Exchanger<String> exchanger = new Exchanger<>();
            ThreadA a = new ThreadA(exchanger);
            ThreadB b = new ThreadB(exchanger);
            a.start();
            b.start();
        }
    }

![在这里插入图片描述][20200622202717976.png]  
exchange(V x, long timeout, TimeUnit unit)与超时：

当调用 exchange(Vx, long timeout, TimeUnit unit)方法后在指定的时间内没有其他线程获取数据,则出现超时异常。

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NvbGRfX19wbGF5_size_16_color_FFFFFF_t_70 1]

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[20200622202717976.png]: /images/20210813/16a7bb93d754447aa5569b260aa1b9fc.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NvbGRfX19wbGF5_size_16_color_FFFFFF_t_70 1]: /images/20210813/08ab4aa2749f4663969a7b29c72ea213.png