Java實現異步處理HTTP請求_方式二：通過DeferredResult

1、DeferredResult

spring 支持http異步返回

2、異步處理

開啓新線程，處理數據並賦值返回。

3、代碼示例

1）controller

package com.liuxd.controller;

import com.liuxd.entity.Responses;
import com.liuxd.service.TaskService2;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.context.request.async.DeferredResult;

@Slf4j
@RestController
public class AsyncCtr2 {

    @Autowired
    private TaskService2 taskService2;

    @GetMapping(value = "/getResult")
    public DeferredResult<Responses<String>> getResult() {
        log.info("收到HTTP請求...");
        long startTime = System.currentTimeMillis();

        DeferredResult<Responses<String>> deferredResult = new DeferredResult<Responses<String>>();

        new Thread(new Runnable() {
            @Override
            public void run() {
                taskService2.getData(deferredResult);
            }
        }).start();

        log.info("接收HTTP請求線程任務已完成,退出!");
        long endTime = System.currentTimeMillis();
        log.info("http請求總耗時： " + (endTime - startTime) + "ms");

        return deferredResult;

    }
}

2）service

package com.liuxd.service;

import com.liuxd.entity.Responses;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;
import org.springframework.web.context.request.async.DeferredResult;

@Slf4j
@Service
public class TaskService2 {

    public void getData(DeferredResult<Responses<String>> deferredResult) {

        log.info("調用service異步有返回方法，開始執行...");
        long startTime = System.currentTimeMillis();

        try {
            Thread.sleep(2500L);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        log.info("調用service異步有返回方法，執行結束！！");

        long endTime = System.currentTimeMillis();
        log.info("調用service異步有返回方法總耗時： " + (endTime - startTime) + "ms");

        deferredResult.setResult(new Responses<>(0, "異步處理完成", "SUCCESS"));

    }


}

3）Responses

package com.liuxd.entity;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class Responses<T> {

    private Integer code;

    private String msg;

    private T data;

}

4）打印結果

5）結果分析

1）http主線程接受請求，處理完請求後線程結束

2）異步線程結束後，返回