下面介绍一些线程编程例子：
1.有一个任务（有三个阶段-前期准备，任务完成，后期检查），要求多个工作者参与共同完成，每个阶段必须所有的工作者完成后才可以进行下一个阶段，三个阶段都完成，总部（一个特殊的工作者）完成后期总结。
CyclicBarrier:故障点，可以重复使用---await
static class SummaryService {
private Random random;
SummaryService(Random random) {
this.random = random;
}
void doService(String name, String phase) {
System.out
.println("-----------------------------------------------");
System.out.println("任务阶段:" + phase + ",当期工作者:" + name + ",正在汇总数据");
try {
Thread.currentThread().sleep(random.nextInt(300));
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("任务阶段:" + phase + ",当期工作者:" + name + ",汇总数据完成");
System.out
.println("-----------------------------------------------");
}
}
static class DataTask implements Runnable {
private String name;
private CyclicBarrier barrier;
private SummaryService service;
DataTask(String name, CyclicBarrier barrier, SummaryService service) {
this.name = name;
this.barrier = barrier;
this.service = service;
}
@Override
public void run() {
service.doService(name, "前期任务准备");
System.out.println("体系单位:[" + name
+ "]汇总[前期任务准备都已完成],等待进入[完成任务阶段],未完成前期的单位还有:"
+ barrier.getNumberWaiting() + "个");
try {
barrier.await();
} catch (InterruptedException | BrokenBarrierException e) {
e.printStackTrace();
}
service.doService(name, "完成任务");
System.out.println("体系单位:[" + name
+ "]汇总[完成任务工作都已完成],等待进入[监控任务阶段],未完成前期的单位还有:"
+ barrier.getNumberWaiting() + "个");
try {
barrier.await();
} catch (InterruptedException | BrokenBarrierException e) {
e.printStackTrace();
}
service.doService(name, "监控任务阶段");
System.out.println("体系单位:[" + name + "]汇总[监控任务阶段都已完成]"
+ barrier.getNumberWaiting() + "个");
try {
barrier.await();
} catch (InterruptedException | BrokenBarrierException e) {
e.printStackTrace();
}
}
}
public static void main(String[] args) throws InterruptedException,
IOException {
CyclicBarrier barrier = new CyclicBarrier(3, new Runnable() {
@Override
public void run() {
System.out.println("总部汇总工作！！！");
}
});
SummaryService service = new SummaryService(new Random());
new Thread(new DataTask("A单位", barrier, service)).start();
new Thread(new DataTask("B单位", barrier, service)).start();
new Thread(new DataTask("C单位", barrier, service)).start();
}
2.CountDownLatch --await(等待所有的任务完成),countDown（某一个任务已经完成）-不可重复使用
static class CTask implements Runnable {
private String name;
private CountDownLatch countDownLatch;
CTask(String name,CountDownLatch countDownLatch) {
this.name = name;
this.countDownLatch = countDownLatch;
}
@Override
public void run() {
System.out.println("工作者:" + name + "处理任务....");
countDownLatch.countDown();
}
}
public static void main(String[] args) throws InterruptedException,
IOException {
final CountDownLatch countDownLatch = new CountDownLatch(3);
new Thread(new CTask("小云", countDownLatch )).start();
new Thread(new CTask("小航", countDownLatch )).start();
new Thread(new CTask("小月", countDownLatch )).start();
countDownLatch.await();
System.out.println("任务都已完成！！");
}
3.exchanger-交换器（分片思想）
public static void main(String[] args) throws InterruptedException,
IOException {
final Exchanger exchanger = new Exchanger();
new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.currentThread().sleep(1000);
System.out.println("换出数据:A,换回的数据:" + exchanger.exchange("A") );
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}).start();
new Thread(new Runnable() {
@Override
public void run() {
try {
System.out.println("换出数据:B,换回的数据:" + exchanger.exchange("B") );
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}).start();
}