以springboot项目举例

1.pom添加maven依赖

<dependency>  <groupId>com.squareup.okhttp3</groupId>  <artifactId>okhttp</artifactId>  <version>你的OkHttp版本</version>  
</dependency>

2.创建OkHttp工具类：
接下来，创建一个Java类来封装OkHttp的使用。这个类可以是一个Spring组件（例如，使用@Component注解），但通常它只是一个普通的Java类就足够了，因为它不依赖于Spring容器中的其他bean。

import okhttp3.OkHttpClient;  
import okhttp3.Request;  
import okhttp3.Response;  
import org.slf4j.Logger;  
import org.slf4j.LoggerFactory;  import java.io.IOException;  
import java.util.concurrent.TimeUnit;  public class OkHttpUtil {  private static final Logger logger = LoggerFactory.getLogger(OkHttpUtil.class);  private static final OkHttpClient client = new OkHttpClient.Builder()  .connectTimeout(30, TimeUnit.SECONDS)  .readTimeout(30, TimeUnit.SECONDS)  .writeTimeout(30, TimeUnit.SECONDS)  .build();  private OkHttpUtil() {  // 私有构造函数，防止实例化  }  //有些小伙伴奇怪为什么没有带参的get请求，因为基础get都不支持//正常都会拼进url里，可以看最下方service调用类的例子，就拼了参数public static String get(String url) throws IOException {  Request request = new Request.Builder()  .url(url)  .build();  try (Response response = client.newCall(request).execute()) {  if (!response.isSuccessful()) {  throw new IOException("Unexpected code " + response);  }  return response.body().string();  }  }  // 可选的：添加带有请求头的get方法  public static String getWithHeaders(String url, Headers headers) throws IOException {  Request request = new Request.Builder()  .url(url)  .headers(headers)  .build();  try (Response response = client.newCall(request).execute()) {  if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);  return response.body().string();  }  } // POST方法：  public static String post(String url, String json) throws IOException {  RequestBody body = RequestBody.create(json, MediaType.parse("application/json; charset=utf-8"));  Request request = new Request.Builder()  .url(url)  .post(body)  .build();  try (Response response = client.newCall(request).execute()) {  if (!response.isSuccessful()) {  throw new IOException("Unexpected code " + response);  }  return response.body().string();  }  }  // PUT 方法  public static String put(String url, String json) throws IOException {  RequestBody body = RequestBody.create(json, MediaType.parse("application/json; charset=utf-8"));  Request request = new Request.Builder()  .url(url)  .put(body)  .build();  try (Response response = client.newCall(request).execute()) {  if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);  return response.body().string();  }  }  // DELETE 方法  public static String delete(String url) throws IOException {  Request request = new Request.Builder()  .url(url)  .delete()  .build();  try (Response response = client.newCall(request).execute()) {  if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);  return response.body().string();  }  }  }

3.使用OkHttp工具类：
现在，你可以在你的Spring Boot应用中的任何地方使用这个工具类来发送HTTP请求。例如，在一个服务类中：

import org.springframework.stereotype.Service;  import java.io.IOException;  @Service  
public class MyService {  public void someMethod() {  //不带参数直接请求（一般用不到）//String url = "https://api.example.com/data";  //下方为带参数的情况String baseUrl = "https://api.example.com/data";  String param1 = "value1";  String param2 = "value2";  // 使用HttpUrl.Builder构建带有查询参数的URL  HttpUrl.Builder urlBuilder = HttpUrl.parse(baseUrl).newBuilder();  urlBuilder.addQueryParameter("param1", param1);  urlBuilder.addQueryParameter("param2", param2);  String url = urlBuilder.build().toString();//也可以不用HttpUrl类，直接自己用stringbuiler拼接带参数的String字符串，效率差不多try {  String response = OkHttpUtil.get(url);  // 处理响应  System.out.println(response);  } catch (IOException e) {  // 处理异常  e.printStackTrace();  }  }  
}

以上为最基本的请求工具类与示例，可自行增加注释、返回值处理等内容