working on login improvement from pcb

android/Pictogram/app/src/main/java/com/yottacode/net/RestapiWrapper.java

@@ -159,6 +159,7 @@ public class RestapiWrapper {
         JSONresponse = null;
         Log.e(RestapiWrapper.class.getCanonicalName(),e.getMessage());
       }
+      Log.i(com.yottacode.net.RestapiWrapper.class.getName(), "server answer: " + JSONresponse.toString());
       return JSONresponse;
     }
     public static JSONObject GET(String surl, Hashtable<String, String> params)  throws IOException {
@@ -243,6 +244,7 @@ public class RestapiWrapper {
         @Override
         protected HttpAsyncTaskParams doInBackground(HttpAsyncTaskParams... params) {
             try {
+              Log.i(com.yottacode.net.RestapiWrapper.class.getName(), " asking to the server for " + params[0].url+" params:"+params[0].url_params +" "+params[0].json_params);
                 JSONObject jresult = params[0].request_method.equalsIgnoreCase("GET")
                         ? GET(params[0].url, params[0].url_params)
                         : POST(params[0].url, params[0].request_method, params[0].url_params, params[0].json_params);

android/Pictogram/app/src/main/java/com/yottacode/pictogram/dao/Device.java

@@ -244,7 +244,7 @@ public class Device extends SQLiteOpenHelper {
         while (cursor.moveToNext() && users == null && !user_found) {
             user_found = cursor.getString(1).equalsIgnoreCase(auser);
             if (user_found)
-                if (cursor.getString(2).equals(apwd)) {
+                if (cursor.getString(2)!=null && cursor.getString(2).equals(apwd)) {
                     users = recoverStudents(cursor.getInt(0));
                     if (users.size() == 0)
                         throw new LoginException("Supervisor hasn't got students", LoginException.NO_STUDENTS);
@@ -257,7 +257,7 @@ public class Device extends SQLiteOpenHelper {
             while (cursor.moveToNext() && users == null && !user_found) {
                 user_found = cursor.getString(1).equalsIgnoreCase(auser);
                 if (user_found)
-                    if (cursor.getString(2).equals(apwd)) {
+                    if (cursor.getString(2)!=null && cursor.getString(2).equals(apwd)) {
                         users = new Vector<>(1);
                         users.add(new User(cursor.getInt(0), cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4), cursor.getString(5), cursor.getString(6), cursor.getString(7), cursor.getString(8),
                                 User.NO_SUPERVISOR, "", "", "", "", "", "", "", ""));