package com.xiaoleilu.hutool;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import com.xiaoleilu.hutool.exceptions.NotInitedException;
/**
* 线程同步结束器<br>
* 在完成一组正在其他线程中执行的操作之前，它允许一个或多个线程一直等待。<br>
* 不能保证同时开始
* @author xiaoleilu
*
*/
public class SyncFinisher{
private CountDownLatch countDownLatch;
private Set<Worker> workers = new LinkedHashSet<Worker>();
/**
* 增加工作线程
* @param worker 工作线程
*/
synchronized public void addWorker(Worker worker) {
workers.add(worker);
}
/**
* 开始工作
*/
public void start() {
countDownLatch = new CountDownLatch(workers.size());
for (Worker worker : workers) {
worker.start();
}
}
/**
* 等待所有Worker工作结束，否则阻塞
* @throws InterruptedException
*/
public void await() throws InterruptedException {
if(countDownLatch == null) {
throw new NotInitedException("Please call start() method first!");
}
countDownLatch.await();
}
/**
* 清空工作线程对象
*/
public void clearWorker() {
workers.clear();
}
/**
* @return 并发数
*/
public long count() {
return countDownLatch.getCount();
}
/**
* 工作者，为一个线程
* @author xiaoleilu
*
*/
public abstract class Worker extends Thread {
@Override
public void run() {
try {
work();
} finally {
countDownLatch.countDown();
}
}
public abstract void work();
}
}