didRangeBeaconsInRegion and REST webservice

Question

I'm trying to call a rest service within this method and is returning the following error:

public void didRangeBeaconsInRegion(Collection<Beacon> beacons, Region region) {
  for (Beacon beacon: beacons) {
    logToDisplay( "ok, detectou beacons" );

    RequestParams params = new RequestParams();
    params.put("beaconId", "gass76382hshsfk");
    AsyncHttpClient client = new AsyncHttpClient();
    client.get("http://192.168.1.130:8080/BeaconServer/palestra/listarPalestras", params, new AsyncHttpResponseHandler() {
      // When the response returned by REST has Http response code '200'
      @Override
      public void onSuccess(int arg0, Header[] arg1, byte[] response) {
        try {
          String respString = new String(response, "UTF-8");
          JSONObject obj = new JSONObject(respString);
          JSONArray jsonArray = obj.getJSONArray("palestra");

          for (int i = 0; i < jsonArray.length(); i++) {
            JSONObject jsonObject = jsonArray.getJSONObject(i);
            String nomePalestrante = jsonObject.getString("nomePalestrante");
            String assuntoPalestra = jsonObject.getString("assuntoPalestra");
            String beaconId = jsonObject.getString("beaconId");

            logToDisplay(nomePalestrante + "\r\n" + assuntoPalestra + "\r\n" + beaconId + "\r\n");

            //string+"\r\n";  
          }
        } catch (JSONException e) {
          // TODO Auto-generated catch block
          logToDisplay("JSONException e");
          Toast.makeText(getApplicationContext(),
            "Error Occured [Server's JSON response might be invalid]!",
            Toast.LENGTH_LONG).show();
          e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
          // erro ao converter o array de bytes json para String
          e.printStackTrace();
        }
      }

      // When the response returned by REST has Http response code other than '200'
      @Override
      public void onFailure(int statusCode, Header[] headers, byte[] errorResponse, Throwable e) {
        // Hide Progress Dialog
        // When Http response code is '404'
        if (statusCode == 404) {
          logToDisplay("404 " + errorResponse.toString());
          Toast.makeText(getApplicationContext(),
            "Requested resource not found",
            Toast.LENGTH_LONG).show();
        }
        // When Http response code is '500'
        else if (statusCode == 500) {
          logToDisplay("500 " + errorResponse.toString());
          Toast.makeText(getApplicationContext(),
              "Something went wrong at server end",
              Toast.LENGTH_LONG).show();
        }
        // When Http response code other than 404, 500
        else {
          logToDisplay("outros " + errorResponse.toString());
          Toast.makeText(getApplicationContext(),
              "Unexpected Error occcured! [Most common Error: Device might not be connected to Internet or remote server is not up and running]",
              Toast.LENGTH_LONG).show();
        }
      }
    });
  }
}

And the following error is shown, do not know what else to do

03-29 21:04:16.034: D/BluetoothAdapter(10437): stopLeScan()
03-29 21:04:16.043: D/BluetoothAdapter(10437): startLeScan(): null
03-29 21:04:16.051: D/BluetoothAdapter(10437): onClientRegistered() - status=0 clientIf=5
03-29 21:04:16.322: W/dalvikvm(10437): threadid=15: thread exiting with uncaught exception (group=0x416f9d40)
03-29 21:04:17.185: D/BluetoothAdapter(10437): stopLeScan()
03-29 21:04:17.195: D/BluetoothAdapter(10437): startLeScan(): null
03-29 21:04:17.202: D/BluetoothAdapter(10437): onClientRegistered() - status=0 clientIf=5
03-29 21:04:18.332: D/BluetoothAdapter(10437): stopLeScan()
03-29 21:04:18.340: D/BluetoothAdapter(10437): startLeScan(): null
03-29 21:04:18.347: D/BluetoothAdapter(10437): onClientRegistered() - status=0 clientIf=5
03-29 21:04:19.467: D/BluetoothAdapter(10437): stopLeScan()
03-29 21:04:19.476: D/BluetoothAdapter(10437): startLeScan(): null
03-29 21:04:19.485: D/BluetoothAdapter(10437): onClientRegistered() - status=0 clientIf=5
03-29 21:04:20.618: D/BluetoothAdapter(10437): stopLeScan()
03-29 21:04:20.627: D/BluetoothAdapter(10437): startLeScan(): null
03-29 21:04:20.633: D/BluetoothAdapter(10437): onClientRegistered() - status=0 clientIf=5
03-29 21:04:21.476: E/AndroidRuntime(10437): FATAL EXCEPTION: IntentService[BeaconIntentProcessor]
03-29 21:04:21.476: E/AndroidRuntime(10437): Process: org.altbeacon.beaconreference, PID: 10437
03-29 21:04:21.476: E/AndroidRuntime(10437): java.lang.NullPointerException
03-29 21:04:21.476: E/AndroidRuntime(10437): at org.altbeacon.beaconreference.MonitoringActivity$4.onFailure(MonitoringActivity.java:199)
03-29 21:04:21.476: E/AndroidRuntime(10437): at com.loopj.android.http.AsyncHttpResponseHandler.handleMessage(AsyncHttpResponseHandler.java:319)
03-29 21:04:21.476: E/AndroidRuntime(10437): at com.loopj.android.http.AsyncHttpResponseHandler$ResponderHandler.handleMessage(AsyncHttpResponseHandler.java:138)
03-29 21:04:21.476: E/AndroidRuntime(10437): at android.os.Handler.dispatchMessage(Handler.java:102)
03-29 21:04:21.476: E/AndroidRuntime(10437): at android.os.Looper.loop(Looper.java:136)
03-29 21:04:21.476: E/AndroidRuntime(10437): at android.os.HandlerThread.run(HandlerThread.java:61)
03-29 21:04:21.784: D/BluetoothAdapter(10437): stopLeScan()

score 0 · Answer 1 · answered Apr 01 '15 at 06:06

Since I don't know which line of code is at 199th line, I can only guess what is giving you a NPE. I have checked your code. Most probably you are getting a null error response from REST and it gives you a NPE. Since there is nothing going on onFailure method but errorResponse.toString(), this should be the problem.

You can create a variable like below and use it anywhere you like and you should change "not known"to a something else which will be more meaningful to you.

String errorText = errorResponse != null ? errorResponse.toString() : "not known";

didRangeBeaconsInRegion and REST webservice

1 Answers1