JAVA post请求

String params = "userId=XXX&name=NNNNN"; String responseString = ""; try{          //打开连接     URL url = new URL(apiUrl);     HttpURLConnection connection = (HttpURLConnection) url.openConnection();     connection.setDoOutput(true);     connection.setRequestMethod("POST");     connection.setRequestProperty("Content-Type","application/x-www-form-urlencoded;charset=utf-8");     OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream(), "UTF-8");

    System.out.println("params"+params);     out.write(params);     out.flush();     out.close();

    String strLine = "";     InputStream in = connection.getInputStream();     BufferedReader reader = new BufferedReader(new InputStreamReader(in));     while ((strLine = reader.readLine()) != null) {         responseString += strLine + "\n";     }     in.close();     System.err.print("请求的返回信息："+responseString);

}catch(Exception e){     e.printStackTrace(); }