带有主体的Java后端POST请求发送到Spring端点，该端点返回到另一个URL的重定向

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class Main {
    public static void main(String[] args) {
        try {
            // 设置目标URL
            URL url = new URL("http://example.com/spring-endpoint");

            // 创建连接
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();

            // 设置请求方法为POST
            connection.setRequestMethod("POST");

            // 启用输出流
            connection.setDoOutput(true);

            // 设置请求体
            String requestBody = "Hello, Spring!";
            OutputStream outputStream = connection.getOutputStream();
            outputStream.write(requestBody.getBytes());
            outputStream.flush();
            outputStream.close();

            // 获取响应
            int responseCode = connection.getResponseCode();
            if (responseCode == HttpURLConnection.HTTP_OK) {
                // 获取重定向URL
                String redirectUrl = connection.getHeaderField("Location");
                System.out.println("重定向URL：" + redirectUrl);
            } else {
                System.out.println("请求失败，响应码：" + responseCode);
            }

            // 关闭连接
            connection.disconnect();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}