在Java中，要打印HTTP请求报文，你可以使用Java的网络编程库，例如java.net.HttpURLConnection。以下是一个简单的示例，展示了如何使用HttpURLConnection发送GET请求并打印请求报文：
import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.URL;public class HttpRequestExample { public static void main(String[] args) { try { // 创建URL对象 URL url = new URL("https://api.example.com/data"); // 打开连接 HttpURLConnection connection = (HttpURLConnection) url.openConnection(); // 设置请求方法 connection.setRequestMethod("GET"); // 设置请求头 connection.setRequestProperty("User-Agent", "Mozilla/5.0"); // 打印请求报文 System.out.println("Request Method: " + connection.getRequestMethod()); System.out.println("Request URL: " + connection.getURL()); System.out.println("Request Headers: "); for (String header : connection.getRequestProperties().keySet()) { System.out.println(header + ": " + connection.getRequestProperty(header)); } // 获取响应状态码 int responseCode = connection.getResponseCode(); System.out.println("Response Code: " + responseCode); // 读取响应内容 BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream())); String inputLine; StringBuilder response = new StringBuilder(); while ((inputLine = in.readLine()) != null) { response.append(inputLine); } in.close(); // 输出响应内容 System.out.println("Response Content: " + response.toString()); } catch (IOException e) { e.printStackTrace(); } }}这个示例向https://api.example.com/data发送一个GET请求，并打印请求报文。请注意，这个示例仅适用于简单的GET请求。对于更复杂的请求（如POST请求、包含请求体的请求等），你需要根据需要调整代码。
