配置

spring.mvc.async.request-timeout=20000

代码

@GetMapping("test")
    public String test(){

        try {
            Thread.sleep(60000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println("keep going");
        return "success";
    }

    @GetMapping("test2")
    public Callable<String> test2() {
        return ()-> {
            try {
                Thread.sleep(60000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("keep going");
            return "foobar";
        };
    }

解析

test不生效  test2生效

看看解释，异步请求到达之前的时间量 

当20秒到了，程序睡眠中断。实际就是程序直接跳出

返回503