code: private String getBetweenBoundaryValues(Expression boundExpression)
      {
          if (boundExpression instanceof IdentificationVariable || boundExpression instanceof NumericLiteral
                  || boundExpression instanceof InputParameter)
          {
              Object value = (boundExpression instanceof InputParameter) ? kunderaQuery.getParametersMap().get(
                      (boundExpression).toParsedText()) : boundExpression.toParsedText();
              return value.toString();
          }
          else if (boundExpression instanceof AdditionExpression)
          {
              String leftValue = checkInputParameter(((AdditionExpression) boundExpression).getLeftExpression());
              String rightValue = checkInputParameter(((AdditionExpression) boundExpression).getRightExpression());
  
              return new Integer(Integer.parseInt(leftValue) + Integer.parseInt(rightValue)).toString();
          }
          else if (boundExpression instanceof SubtractionExpression)
          {
              String leftValue = checkInputParameter(((SubtractionExpression) boundExpression).getLeftExpression());
              String rightValue = checkInputParameter(((SubtractionExpression) boundExpression).getRightExpression());
  
              return new Integer(Integer.parseInt(leftValue) - Integer.parseInt(rightValue)).toString();
          }
          else if (boundExpression instanceof MultiplicationExpression)
          {
              String leftValue = checkInputParameter(((MultiplicationExpression) boundExpression).getLeftExpression());
              String rightValue = checkInputParameter(((MultiplicationExpression) boundExpression).getRightExpression());
  
              return new Integer(Integer.parseInt(leftValue) * Integer.parseInt(rightValue)).toString();
          }
  
          else if (boundExpression instanceof DivisionExpression)
          {
              String leftValue = checkInputParameter(((DivisionExpression) boundExpression).getLeftExpression());
              String rightValue = checkInputParameter(((DivisionExpression) boundExpression).getRightExpression());
              return new Integer(Integer.parseInt(leftValue) / Integer.parseInt(rightValue)).toString();
          }
  
          return null;
      }
docs: Gets the between boundary values.
  
  @param boundExpression
  the bound expression
  @return the between boundry values