Android Http请求POST JSON

<uses-permission android:name="android.permission.INTERNET" />

import android.os.AsyncTask;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpPostTask extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... params) {
        String urlString = params[0];
        String jsonData = params[1];
        String result = "";

        try {
            URL url = new URL(urlString);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setRequestMethod("POST");
            connection.setRequestProperty("Content-Type", "application/json");
            connection.setDoOutput(true);

            OutputStream outputStream = connection.getOutputStream();
            outputStream.write(jsonData.getBytes());
            outputStream.flush();
            outputStream.close();

            int responseCode = connection.getResponseCode();
            if (responseCode == HttpURLConnection.HTTP_OK) {
                BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
                String line;
                while ((line = reader.readLine()) != null) {
                    result += line;
                }
                reader.close();
            } else {
                result = "Error: " + responseCode;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        return result;
    }

    @Override
    protected void onPostExecute(String result) {
        // 处理请求结果
    }
}

String url = "https://example.com/api";
String jsonData = "{\"key\":\"value\"}";

HttpPostTask httpPostTask = new HttpPostTask();
httpPostTask.execute(url, jsonData);