Java并发编程 - AQS 之 CountDownLatch（二）

package com.mmall.concurrency.example.aqs;
import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
@Slf4j
public class CountDownLatchExample2 {
    private final static int threadCount = 200;
    public static void main(String[] args) throws Exception {
        ExecutorService exec = Executors.newCachedThreadPool();
        final CountDownLatch countDownLatch = new CountDownLatch(threadCount);
        for (int i = 0; i < threadCount; i++) {
            final int threadNum = i;
            // Thread.sleep(100); // 不能放在这里，必须要在线程池包围内才有效
            exec.execute(() -> {
                try {
                    test(threadNum);
                } catch (Exception e) {
                    log.error("exception", e);
                } finally {
                    countDownLatch.countDown();
                }
            });
        }
        countDownLatch.await(10, TimeUnit.MILLISECONDS);
        log.info("finish");
        exec.shutdown();
    }
    private static void test(int threadNum) throws Exception {
        Thread.sleep(100);
        log.info("{}", threadNum);
    }
}