1. 引入 maven 依赖

<dependency><groupId>org.apache.httpcomponents</groupId><artifactId>httpclient</artifactId>
</dependency>

2. 发送 GET 方式的请求

package com.zxe;import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
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.boot.test.context.SpringBootTest;@SpringBootTest
public class HttpClient {@Testpublic void test() throws Exception {//1.创建httpclient对象CloseableHttpClient httpClient = HttpClients.createDefault();//2.创建请求对象HttpGet httpGet = new HttpGet("http://localhost:8080/user/status");//3.发送请求，接收响应结果CloseableHttpResponse response = httpClient.execute(httpGet);//4.获取服务端返回的状态码int statusCode = response.getStatusLine().getStatusCode();System.out.println("服务端返回的状态码为：" + statusCode);//5.解析响应体HttpEntity entity = response.getEntity();String body = EntityUtils.toString(entity);System.out.println("服务端返回的数据为：" + body);//6.关闭资源response.close();httpClient.close();}}

3. 发送 POST 方式的请求

package com.zxe;import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.json.JSONObject;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;@SpringBootTest
public class HttpClient {@Testpublic void test() throws Exception {//1.创建httpclient对象CloseableHttpClient httpClient = HttpClients.createDefault();//2.创建请求对象HttpPost httpPost = new HttpPost("http://localhost:8080/admin/employee/login");//3.设置请求体参数JSONObject jsonObject = new JSONObject();jsonObject.put("username", "admin");jsonObject.put("password", "123456");StringEntity entity = new StringEntity(jsonObject.toString());entity.setContentEncoding("utf-8");//4.数据格式entity.setContentType("application/json");httpPost.setEntity(entity);//5.发送请求，接收响应结果CloseableHttpResponse response = httpClient.execute(httpPost);//4.获取服务端返回的状态码int statusCode = response.getStatusLine().getStatusCode();System.out.println("服务端返回的状态码为：" + statusCode);//5.解析响应体HttpEntity entity1 = response.getEntity();String body = EntityUtils.toString(entity1);System.out.println("服务端返回的数据为：" + body);//6.关闭资源response.close();httpClient.close();}}