1.2.1 方法exchange()阻塞的特性

類Exchanger中的exchange()方法具有阻塞的特色，也就是此方法被調(diào)用后等待其他線程來取得數(shù)據(jù)，如果沒有其他線程取得數(shù)據(jù)，則一直阻塞等待。

創(chuàng)建測試用的項(xiàng)目Exchanger_1，創(chuàng)建類ThreadA.java代碼如下：

---

        package extthread;
        import java.util.concurrent.Exchanger;
        public class ThreadA extends Thread {
            private Exchanger<String> exchanger;
            public ThreadA(Exchanger<String> exchanger) {
                super();
                this.exchanger = exchanger;
            }
            @Override
            public void run() {
                try {
                    System.out.println("在線程A中得到線程B的值=" + exchanger.exchange("中國人A"));
                    System.out.println("A end! ");
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }

---

運(yùn)行類Run.java代碼如下：

---

        package test.run;
        import java.util.concurrent.Exchanger;
        import extthread.ThreadA;
        public class Run {
            public static void main(String[] args) {
                Exchanger<String> exchanger = new Exchanger<String>();
                ThreadA a = new ThreadA(exchanger);
                a.start();
                System.out.println("main end! ");
            }
        }

---

程序運(yùn)行效果如圖1-29所示。