SpringMVC异步调用,Callable和DeferredResult的使用

Callable和DeferredResult都是springMVC里面的异步调用，Callable主要用来处理一些简单的逻辑，DeferredResult主要用于处理一些复杂逻辑

1.Callable的使用

github地址：https://github.com/showkawa/spring-annotation/blob/master/src/main/java/com/brian/async/Callable01.java

package com.brian.async;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.concurrent.Callable;

/**
 * SpringMVC异步调用 Callable =>执行过程
 * 1.控制器返回Callable
 * 2.Spring异步调用，将Callable提交到TaskExecutor使用一个隔离的线程进行执行
 * 3.DispatcherServlet和所有的Filter退出web容器的线程，而response保持打开的状态
 * 4.Callable返回结果，SpringMVC将请求重新派发给容器，并且恢复之前的处理。
 * 5.根据Callable返回的结果。SpringMVC继续进行试图渲染流程等等等等。
 */
@Controller
public class Callable01 {

    @ResponseBody
    @RequestMapping("/async01")
    public Callable<String> async01() {

        System.out.println("主线程start...." + Thread.currentThread()+"-"+System.currentTimeMillis());
        Callable<String> callable = new Callable<String>() {

            public String call() throws Exception {
                System.out.println("callable线程start...." + Thread.currentThread() + "-" + System.currentTimeMillis());
                Thread.sleep(3000);
                System.out.println("callable线程end...." + Thread.currentThread() + "-" + System.currentTimeMillis());
                return "ok";
            }
        };
        System.out.println("主线程end...." + Thread.currentThread()+"-"+System.currentTimeMillis());
        return callable;
    }

}

2.DeferredResult的使用

github地址：https://github.com/showkawa/spring-annotation/blob/master/src/main/java/com/brian/async/DeferredResult02.java

package com.brian.async;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.context.request.async.DeferredResult;

import java.util.UUID;

/**
 * DeferredResult异步调用
 *
 */
@Controller
public class DeferredResult02 {

    @RequestMapping("/create")
    public DeferredResult<Object> createOrder() {
        DeferredResult<Object> deferredResult =
                new DeferredResult<Object>((long)15000,"create order fail");
        //存放到模拟的队列中
        ResultQueue.add(deferredResult);
        return deferredResult;
    }

    @RequestMapping("/create/action")
    public String createAction() {
        DeferredResult<Object> deferredResult = ResultQueue.get();
        String order = UUID.randomUUID().toString();
        deferredResult.setResult(order);
        return " create order id: " + order;
    }

}