Java之Exchanger使用

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1、此类的功能以及使用场景
a、此类提供对外的操作是同步的；
b、用于成对出现的线程之间交换数据；
c、可以视作双向的同步队列；
d、可应用于基因算法、流水线设计等场景。

2、示例程序(生产者与消费者的流水线生产)

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package com.iseach.jdk.base.thread;
import java.util.concurrent.Exchanger;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.logging.Logger;
public class ExchangerTest {
    protected static final Logger log = Logger.getLogger(ExchangerTest.class.getSimpleName());
    private static volatile boolean isDone = false;
    static class ExchangerProducer implements Runnable {
        private Exchanger<Integer> exchanger;
        private static int data = 1;
        ExchangerProducer(Exchanger<Integer> exchanger) {
            this.exchanger = exchanger;
        }
        @Override
        public void run() {
            while (!Thread.interrupted() && !isDone) {
                for (int i = 1; i <= 3; i++) {
                    try {
                        TimeUnit.SECONDS.sleep(1);
                        data = i;
                        System.out.println(System.currentTimeMillis()+"producer before: " + data);
                        data = exchanger.exchange(data);
                        System.out.println(System.currentTimeMillis()+"producer after: " + data);
                    } catch (InterruptedException e) {
                       
                    }
                }
                isDone = true;
            }
        }
    }
    static class ExchangerConsumer implements Runnable {
        private Exchanger<Integer> exchanger;
        private static int data = 0;
        ExchangerConsumer(Exchanger<Integer> exchanger) {
            this.exchanger = exchanger;
        }
        @Override
        public void run() {
            while (!Thread.interrupted() && !isDone) {
                data = 0;
                System.out.println(System.currentTimeMillis()+"consumer before : " + data);
                try {
                    TimeUnit.SECONDS.sleep(1);
                    data = exchanger.exchange(data);
                } catch (InterruptedException e) {
                    
                }
                System.out.println(System.currentTimeMillis()+"consumer after : " + data);
            }
        }
    }
    public static void main(String[] args) {
        ExecutorService exec = Executors.newCachedThreadPool();
        Exchanger<Integer> exchanger = new Exchanger<Integer>();
        ExchangerProducer producer = new ExchangerProducer(exchanger);
        ExchangerConsumer consumer = new ExchangerConsumer(exchanger);
        exec.execute(producer);
        exec.execute(consumer);
        exec.shutdown();
        try {
            exec.awaitTermination(30, TimeUnit.SECONDS);
        } catch (InterruptedException e) {
            
        }
    }
}