java怎么调用restful接口

Java可以使用多种方式调用RESTful接口，以下是其中几种常见的方法：

使用Java原生的HttpURLConnection类来发送HTTP请求：

import java.io.BufferedReader;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.URL;public class RestClient {public static void main(String[] args) {try {URL url = new URL("http://example.com/api/resource");HttpURLConnection conn = (HttpURLConnection) url.openConnection();conn.setRequestMethod("GET");BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));String line;StringBuilder response = new StringBuilder();while ((line = reader.readLine()) != null) {response.append(line);}reader.close();System.out.println(response.toString());conn.disconnect();} catch (Exception e) {e.printStackTrace();}}}

使用第三方库，如Apache HttpClient或OkHttp：

使用Apache HttpClient的示例：

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.HttpClientBuilder;import org.apache.http.util.EntityUtils;public class RestClient {public static void main(String[] args) {try {HttpClient client = HttpClientBuilder.create().build();HttpGet request = new HttpGet("http://example.com/api/resource");HttpResponse response = client.execute(request);HttpEntity entity = response.getEntity();String responseBody = EntityUtils.toString(entity);System.out.println(responseBody);} catch (Exception e) {e.printStackTrace();}}}

使用OkHttp的示例：

import okhttp3.OkHttpClient;import okhttp3.Request;import okhttp3.Response;public class RestClient {public static void main(String[] args) {try {OkHttpClient client = new OkHttpClient();Request request = new Request.Builder().url("http://example.com/api/resource").build();Response response = client.newCall(request).execute();String responseBody = response.body().string();System.out.println(responseBody);} catch (Exception e) {e.printStackTrace();}}}

这些示例代码可以根据具体的需求进行修改和扩展。