异步执行

1 需要线程返回信息

public void execute(){
        //来一个线程池
        ExecutorService executor = Executors.newFixedThreadPool(2);
        CompletableFuture<Integer> future1= CompletableFuture.supplyAsync(new Supplier<Integer>()
        {
            @Override
            public Integer get() {
                for(int i=0;i<10;i++) {
                    System.out.println("task1:"+i);
                    sleep(1000);
                }
                
                return 333;
            }
        },executor);
        
        
        CompletableFuture<Integer> future2 =CompletableFuture.supplyAsync(new Supplier<Integer>()
        {
            @Override
            public Integer get() {
                for(int i=0;i<10;i++) {
                    System.out.println("task2:"+i);
                    sleep(1000);
                }
                return 666;
            }
        },executor);
        
        //等待所有任务执行结束
        CompletableFuture<Void> all= CompletableFuture.allOf(future1,future2);
        all.thenAccept(e->{
            //关闭线程池
            executor.shutdown();
            System.out.println("执行结束");
           
        });
}

    static void sleep(long millis) {
        try {
            Thread.sleep(millis);
        }
        catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

2 仅执行

//线程池
        ExecutorService executor = Executors.newFixedThreadPool(2);
        
     
        CompletableFuture<Void> future1= CompletableFuture.runAsync(()->{
           
        },executor);
        
        CompletableFuture<Void> future2 =CompletableFuture.runAsync(()->{
        
        },executor);
        
        //等待完成
        try {
            CompletableFuture.allOf(future1,future2).get();
        }
        catch (InterruptedException|ExecutionException e ) {
            e.printStackTrace();
        }
        executor.shutdown();
        System.out.println("执行完毕");

线程池执行业务，模板

@Test
	public void test() {
		// 开50线程执行
		ExecutorService executor = Executors.newFixedThreadPool(50);
		
		//计数器
		AtomicInteger cnt = new AtomicInteger(0);

		//业务数据
		List<String> list = new ArrayList<>();
		for (int i = 0; i < 99; i++) {
			list.add("sss" + i + 1);
		}

		// 阻塞线程计数器
		CountDownLatch countDownLatch = new CountDownLatch(list.size());

		for (String s : list) {
			// 异步执行
			executor.execute(() -> {
				
				// do something
				try {
					System.out.println("第" + cnt.getAndAdd(1) + "个，ok，"+s);
				} catch (Exception e) {
					System.out.println("第" + cnt.getAndAdd(1) + "个失败，"+s);
				} finally {
					countDownLatch.countDown();
				}

			});

		}

		// countDownLatch计数阻塞
		try {
			countDownLatch.await();
		} catch (InterruptedException e) {
			e.printStackTrace();
		}

		System.out.println("===结束===");
		// 关闭线程池
		executor.shutdown();
	}