使用
CyclicBarrier
. 以下是其Javadoc中的相关引用:
一种同步辅助工具,允许一组线程都等待彼此到达一个共同的障碍点。cyclicbarrier在涉及固定大小的线程组的程序中很有用,这些线程偶尔必须等待对方。这个屏障被称为循环的,因为它可以在等待的线程被释放后重新使用。
所以,你需要创建一个
篱栅
2
并让接收方线程调用
await()
在确认之后,让发送方线程调用
等待()
在发送之前。
这里有一个
SSCCE
让你开始。
package com.stackoverflow.q3379797;
import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class Test {
public static void main(String[] args) {
CyclicBarrier barrier = new CyclicBarrier(2);
Receiver receiver = new Receiver(barrier);
Sender sender = new Sender(barrier);
ExecutorService executor = Executors.newFixedThreadPool(2);
executor.submit(receiver);
executor.submit(sender);
}
}
class Receiver implements Runnable {
private CyclicBarrier barrier;
public Receiver(CyclicBarrier barrier) {
this.barrier = barrier;
}
@Override
public void run() {
while (true) {
try {
// Wait for ACK (the sleep just simulates that).
Thread.sleep(2000);
System.out.println("ACK");
// Then notify.
barrier.await();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
class Sender implements Runnable {
private CyclicBarrier barrier;
public Sender(CyclicBarrier barrier) {
this.barrier = barrier;
}
@Override
public void run() {
while (true) {
try {
// Wait for notify.
barrier.await();
// Now do SEND.
System.out.println("SEND");
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
您将在stdout中看到以下内容:
(2 seconds)
ACK
SEND
(2 seconds)
ACK
SEND
(2 seconds)
ACK
SEND