public String Post(String content, String charset, String url) {

        try {

            URL u = new URL(url);

            HttpURLConnection http = (HttpURLConnection) u.openConnection();

            

            /*

            http.setDoOutput(true);

            http.setDoInput(true);

            http.setRequestMethod("POST");

            http.setConnectTimeout(50000);

            http.setReadTimeout(50000);

            http.connect();

            

            OutputStream output = http.getOutputStream();

            output.write(content.getBytes());

            output.flush();

            output.close();

            */

            

            //如果吧注释取消掉就出现了严重: null

java.io.IOException: Server returned HTTP response code: 500 for URL: 问题出在哪呢





            System.out.println(http.getResponseCode());

            StringBuilder sb = new StringBuilder();

            BufferedReader in;

            if (charset != null) {

                in = new BufferedReader(new InputStreamReader(http.getInputStream(), charset));

            } else {

                in = new BufferedReader(new InputStreamReader(http.getInputStream()));

            }



            String line = "";

            while ((line = in.readLine()) != null) {

                sb.append(line).append("\n");

            }

            in.close();

            http.disconnect();

            return sb.toString();

        } catch (Exception ex) {

            Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);

            System.out.println(url + " Post ");

            return null;

        }

    }