Java并发工具：CountDownLatch应用示例-蒲公英云

Java并发工具：CountDownLatch应用示例

CountDownLatch是Java并发编程中的一个工具类，主要用于协调多个线程的执行。当count为0时，会触发一个屏障，所有等待该屏障的线程都会被唤醒。

下面是一个简单的CountDownLatch应用示例：

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
public class CountDownLatchExample {
    private CountDownLatch countDownLatch;
    public CountDownLatchExample(int initialCount) {
        this.countDownLatch = new CountDownLatch(initialCount);
    }
    // producer thread
    public void produce() throws InterruptedException {
        for (int i = 0; i < 10; i++) {
            System.out.println("Produce: " + i);
            countDownLatch.countDown();
        }
        System.out.println("Producer done.");
    }
    // consumer thread
    public void consume() throws InterruptedException {
        System.out.println("Consume start.");
        countDownLatch.await(5, TimeUnit.SECONDS)); // wait for 5 seconds or until count reaches zero
        if (countDownLatch.getCount() == 0) {
            System.out.println("All consumers done.");
        } else {
            System.out.println("Some consumers still running.");
        }
    }
    public static void main(String[] args) {
        CountDownLatchExample example = new CountDownLatchExample(10); // initial count is 10
        new Thread(example::produce).start(); // producer thread
        new Thread(example::consume).start(); // consumer thread
    }
}