CompletableFuture执行多个异步任务,将结果合并返回

柔情只为你懂 2024-03-24 17:40 9阅读 0赞

public Map<String, String> test() throws InterruptedException, ExecutionException {
    	// 不存在并发插入情况，不需要使用ConcurrentHashMap
    //		Map<String, String> data = new ConcurrentHashMap<>(3);
    	Map<String, String> data = new HashMap<>(3);
    	//第一个任务。返回参数类型可自定义
    	CompletableFuture<String> task01 = CompletableFuture.supplyAsync(() -> {
    		try {
    			TimeUnit.SECONDS.sleep(3);
    		} catch (InterruptedException e) {
    			e.printStackTrace();
    		}
    		return "task01";
    	});
    	//第二个任务。返回参数类型可自定义
    	CompletableFuture<String> task02 = CompletableFuture.supplyAsync(() -> {
    		try {
    			TimeUnit.SECONDS.sleep(5);
    		} catch (InterruptedException e) {
    			e.printStackTrace();
    		}
    		return "task02";
    	});
    	// 第三个任务。返回参数类型可自定义
    	CompletableFuture<String> task03 = CompletableFuture.supplyAsync(() -> {
    		try {
    			TimeUnit.SECONDS.sleep(3);
    		} catch (InterruptedException e) {
    			e.printStackTrace();
    		}
    		return "task03";
    	});
    	// get()方法会阻塞，最终得到处理时间，取决于多线程的最大响应时间的接口
    	String task01Result = task01.get() ;
    	String task02Result = task02.get() ;
    	String task03Result = task03.get() ;
    	data.put("task01", task01Result );
    	data.put("task02", task02Result );
    	data.put("task03", task03Result );
    	return data;
    }