异步任务组合神器CompletableFuture

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使用Demo

import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicInteger;public class CompletableFutureDemo {private static AtomicInteger count = new AtomicInteger(2);public static void main(String[] args) throws InterruptedException, ExecutionException {// 准备10个线程ExecutorService executorService = Executors.newFixedThreadPool(2);long start = System.currentTimeMillis();// 模拟处理订单CompletableFuture<Void> dealOrder = CompletableFuture.runAsync(() -> {// 模拟任务耗时 0~4秒try {int seconds = ThreadLocalRandom.current().nextInt(5);TimeUnit.SECONDS.sleep(seconds);System.out.println("task is completed! cost:" + seconds + "s left: " + count.decrementAndGet());} catch (InterruptedException e) {e.printStackTrace();}}, executorService);// 模拟处理库存CompletableFuture<Void> dealStock = CompletableFuture.runAsync(() -> {// 模拟任务耗时 0~4秒try {int seconds = ThreadLocalRandom.current().nextInt(5);TimeUnit.SECONDS.sleep(seconds);System.out.println("task is completed! cost:" + seconds + "s left: " + count.decrementAndGet());} catch (InterruptedException e) {e.printStackTrace();}}, executorService);// 可变参数，可以传任意个CompletableFuture，阻塞等待所有任务完成CompletableFuture.allOf(dealOrder, dealStock).get();// 最终全部任务完成，总耗时取决于最耗时的任务时长System.out.println("all task is completed! cost: " + (System.currentTimeMillis() - start) + "ms");}
}