SpringBoot ： 使用SpringBoot 实现HTTP请求（post/get）

使用SpringBoot 实现了HTTP请求（post/get）,总结如下

HTTPRequest 请求工具类

package com.aliyun.mq.util;

import org.springframework.http.*;
import org.springframework.http.client.SimpleClientHttpRequestFactory;
import org.springframework.util.MultiValueMap;
import org.springframework.web.client.HttpClientErrorException;
import org.springframework.web.client.RestTemplate;

import java.io.IOException;


public class HttpRestUtils {

    /**
     * http post
     * */
    public static String post(String url, MultiValueMap<String, String> params) throws IOException {
        return  httpRestClient(url, HttpMethod.POST, params);
    }

    /**
     * http get
     * */
    public static String get(String url, MultiValueMap<String, String> params) throws IOException {
        return  httpRestClient(url, HttpMethod.POST, params);
    }

    /**
     * HttpMethod  post/get
     * */
    private static String httpRestClient(String url, HttpMethod method, MultiValueMap<String, String> params) throws IOException {
        SimpleClientHttpRequestFactory requestFactory = new SimpleClientHttpRequestFactory();
        requestFactory.setConnectTimeout(10*1000);
        requestFactory.setReadTimeout(10*1000);
        RestTemplate client = new RestTemplate(requestFactory);
        HttpHeaders headers = new HttpHeaders();
        //headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
        headers.setContentType(MediaType.APPLICATION_JSON_UTF8);
        HttpEntity<MultiValueMap<String, String>> requestEntity = new HttpEntity<MultiValueMap<String, String>>(params, headers);
        //  执行HTTP请求
        ResponseEntity<String> response = null;
        try{
            response = client.exchange(url, HttpMethod.POST, requestEntity, String.class);
            return response.getBody();
        }
        catch (HttpClientErrorException e){
            System.out.println( "------------- 出现异常 HttpClientErrorException -------------");
            System.out.println(e.getMessage());
            System.out.println(e.getStatusText());
            System.out.println( "-------------responseBody-------------");
            System.out.println( e.getResponseBodyAsString());
            e.printStackTrace();
            return "";
        }
        catch (Exception e) {
            System.out.println( "------------- HttpRestUtils.httpRestClient() 出现异常 Exception -------------");
            System.out.println(e.getMessage());
            return "";
        }
    }
}

工具类使用案例

import com.aliyun.mq.util.HttpRestUtils; 
import org.springframework.http.HttpMethod;
import org.springframework.stereotype.Service;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import javax.annotation.Resource;
import java.util.Date;

public String PostData()
    {
        try{
            //api url地址
            String url = "http://127.0.0.1:8082/test/respost";
            //post请求
            HttpMethod method =HttpMethod.POST;
            // 封装参数，千万不要替换为Map与HashMap，否则参数无法传递
            MultiValueMap<String, String> params= new LinkedMultiValueMap<String, String>();
            params.add("name", "wangru");
            params.add("sex", "男");
            params.add("age", "27");
            params.add("address", "Jinan China");
            params.add("time", new Date().toString());
            System.out.print("发送数据："+params.toString());
            //发送http请求并返回结果
            String result = HttpRestUtils.post(url,params);
            System.out.print("接收反馈："+result);
            return result;
        }catch (Exception e){
            System.out.println( "------------- "+this.getClass().toString()+".PostData() : 出现异常 Exception -------------");
            System.out.println(e.getMessage());
            return "";
        }
    }

发送和接收请求

import com.aliyun.mq.service.MqService;
import com.aliyun.mq.util.JsonUtils;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

@RequestMapping("/test")
@RestController
public class IndexController {

    /**
     * 响应post请求
     * @return
     */
    @RequestMapping(value = "/respost", method = RequestMethod.POST)
    public String respost(){
        return "response post success";
    }


    /**
     * 发出post请求
     * @return
     */
    @GetMapping("/reqpost")
    public String reqpost(){
        System.out.println("this.getClass(): " + this.getClass().toString());
        String svalue = mqService.PostData();
        return svalue;
    }
}

遇到的问题总结：

1、405 Method not allowed ， Request method 'POST' not supported

解决：在@RequestMapping中Method 没有指定为post。 即要加上  @RequestMapping(value = "/test/respost", method = RequestMethod.POST)

2、出现 Message Not  Found

解决： 因为 @RequestMapping(value = "/test/respost", method = RequestMethod.POST) 中的 value 值错误，导致无法找到入口地址，更改为 @RequestMapping(value = "/respost", method = RequestMethod.POST) 就成功