如何在Java中获取HTTP错误400的响应json

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

public class HttpErrorHandlingExample {
    public static void main(String[] args) {
        try {
            // 创建URL对象
            URL url = new URL("http://example.com/api");

            // 建立HTTP连接
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();

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

            // 发送HTTP请求
            int responseCode = connection.getResponseCode();

            // 检查响应状态码
            if (responseCode == HttpURLConnection.HTTP_BAD_REQUEST) {
                // 获取错误响应JSON
                BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getErrorStream()));
                String line;
                StringBuilder responseJson = new StringBuilder();
                while ((line = reader.readLine()) != null) {
                    responseJson.append(line);
                }
                reader.close();

                // 在这里处理错误响应JSON
                System.out.println("错误响应JSON：" + responseJson.toString());
            } else {
                // 处理其他响应状态码
                // ...
            }

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