sending JSON object using POST Methods

Question

  @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Intent in=getIntent();

        Uri uri=in.getData();

            // l.setText(uri.toString());
             String p=uri.getQueryParameter(OAuth.OAUTH_VERIFIER);
             CreateFolderActivity.m_provider.setOAuth10a(true);
             try {
                CreateFolderActivity.m_provider.retrieveAccessToken(p);
            } catch (OAuthMessageSignerException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (OAuthNotAuthorizedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (OAuthExpectationFailedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (OAuthCommunicationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
             URL url = null;
                try {
                    url = new URL("http://api.mendeley.com/oapi/library/folders?consumer_key=" + CreateFolderActivity.m_consumer_key);


                } catch (MalformedURLException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }
                HttpURLConnection hc=null;
                try {
                    hc=(HttpURLConnection)url.openConnection();
                    try {CreateFolderActivity.m_consumer.sign(hc);

                        hc.setRequestMethod("POST");
                        hc.setDoInput(true);
                        hc.setDoOutput(true);
                        hc.setUseCaches(false); 

                        hc.setRequestProperty("Content-type","text/json; charset=utf-8"); 
                        OutputStreamWriter wr = new OutputStreamWriter(hc.getOutputStream());
                        wr.write("folder = {'name' : 'Test creation folder'}");

                        wr.flush();

                        // Get the response
                     /*   BufferedReader rd = new BufferedReader(new InputStreamReader(hc.getInputStream()));
                        String strResponse = null;
                        for (String strLine = ""; strLine != null; strLine = rd.readLine()) 
                            strResponse += strLine ;*/
                        Log.i("HelloWorld",hc.getResponseMessage()+"    "+hc.getResponseCode());
                    } catch (OAuthMessageSignerException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (OAuthExpectationFailedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }


  }
  }`

hi i am trying to send a json Object using post method here above is code but i am getting internal server error 500.i read its appear when u send some unexpected data.Actually its an OAuth implementation and i have to add a folder in the user account.and i retrieve access token successfully.please suggest what is wrong in code

Solution

• "folder = {'name' : 'Test creation folder'}" is invalid JSON. JSON Strings must be enclosed with double-quotes ("). I think you meant this:

  {
      "folder": {
          "name": "Test creation folder"
      }
  }
  

  1. Refer to the JSON specification.
  2. Validate your JSON.
  3. Pretty print your JSON.

• The correct JSON mime type is application/json.

• Don't build your JSON by hand. Use the org.json package. Start by looking at JSONObject and JSONArray.

Example:

hc.setRequestProperty("content-type","application/json; charset=utf-8"); 
OutputStreamWriter wr = new OutputStreamWriter(hc.getOutputStream());
JSONObject data = new JSONObject().put("folder",
                  new JSONObject().put("name", "test creation folder"));
wr.write(data.toString());