1.HttpClient
1.HttpClient 是 Apache Jakarta Common 下的子项目，用来提供高效的、最新的、功能丰富的反对 HTTP 协定的客户端编程工具包
业务需要阐明
- HttpClient入门案例
1）### 导入jar包
2）### HttpClient入门案例
package com.jt.test;import com.sun.scenario.effect.impl.sw.sse.SSEBlend_SRC_OUTPeer;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.client.HttpClient;import org.apache.http.client.methods.HttpGet;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClients;import org.apache.http.util.EntityUtils;import org.junit.jupiter.api.Test;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.test.context.SpringBootTest;import java.io.IOException;//@SpringBootTest //从spring容器中获取bean对象,之后实现测试业务.public class TestHttpClient { /** * 1.实例化HttpClient对象 * 2.定义近程拜访的url地址 * 3.定义申请类型的对象 * 4.发动http申请,获取响应的后果 * 5.对返回值后果进行校验.获取实在的数据信息. * */ @Test public void testGet() throws IOException { HttpClient httpClient = HttpClients.createDefault(); String url = "http://www.baidu.com"; HttpGet httpGet = new HttpGet(url); HttpResponse httpResponse = httpClient.execute(httpGet); //常见后果状态 200 404 406参数异样 500后端服务器异样 504超时 502拜访的网址不存在 //获取状态码 int status = httpResponse.getStatusLine().getStatusCode(); if(status == 200){ //获取响应后果 HttpEntity entity = httpResponse.getEntity(); String result = EntityUtils.toString(entity,"UTF-8"); System.out.println(result); } }}3.HttpClient实现业务逻辑（前端【controller--service】--后端【controller--service】）
1）### 业务需要
用户通过http://www.jt.com/user/testHt...
JT-WEB服务器 拜访JT-SSO时的申请http://sso.jt.com/user/testHt...
2）### 编辑前端Controller
@RequestMapping("/testHttpClient") @ResponseBody public List<User> testHttpClient(){ return userService.testHttpClient(); }3) ### 编辑前端Service
package com.jt.service;import com.jt.pojo.User;import com.jt.util.ObjectMapperUtil;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.client.HttpClient;import org.apache.http.client.methods.HttpGet;import org.apache.http.impl.client.HttpClients;import org.apache.http.util.EntityUtils;import org.springframework.stereotype.Service;import java.io.IOException;import java.util.ArrayList;import java.util.Date;import java.util.LinkedHashMap;import java.util.List;@Servicepublic class UserServiceImpl implements UserService{ @Override public List<User> testHttpClient() { List userList = new ArrayList<>(); //由jt-web服务器去链接jt-sso的服务器 String url = "http://sso.jt.com/user/testHttpClient"; HttpClient httpClient = HttpClients.createDefault(); HttpGet httpGet = new HttpGet(url); try { HttpResponse httpResponse =httpClient.execute(httpGet); if(httpResponse.getStatusLine().getStatusCode() == 200){ HttpEntity httpEntity = httpResponse.getEntity(); String result = EntityUtils.toString(httpEntity, "UTF-8"); userList = ObjectMapperUtil.toObject(result, userList.getClass()); /* for (LinkedHashMap<String,Object> map : userList){ User userTemp = new User(); userTemp.setId( Long.parseLong(map.get("id")+"")); userTemp.setUsername((String)map.get("username")); userTemp.setPassword((String)map.get("password")); userTemp.setPhone((String)map.get("phone")); userTemp.setEmail((String)map.get("phone")); userList2.add(userTemp); }*/ } } catch (IOException e) { e.printStackTrace(); throw new RuntimeException(e); } return userList; }}4) ### 编辑后端Controller
/** * http://sso.jt.com/user/testHttpClient * 返回List<User> */ @RequestMapping("testHttpClient") public List<User> testHttpClient(){ return userService.findAll(); }5) ### 编辑后端Service
@Override public List<User> findAll() { return userMapper.selectList(null); }