code: protected String getResult() {
          // Until read end
          while (!isDone) {
              try {
                  Thread.sleep(500);
              } catch (InterruptedException e) {
                  e.printStackTrace();
              }
          }
  
          // Get return value
          if (mResult.length() == 0)
              return null;
          else
              return mResult.toString();
      }
docs: Get Result
  
  @return Result