code: @Override
  	public Object evaluate(Message message) throws JMSException
      {
          Number value = leftOperand.evaluateNumeric(message);
          Number lowerBound = lowerBoundOperand.evaluateNumeric(message);
          Number upperBound = upperBoundOperand.evaluateNumeric(message);
          if (value == null || lowerBound == null || upperBound == null)
              return null;
          
          return ArithmeticUtils.greaterThanOrEquals(value, lowerBound).booleanValue() &&
                 ArithmeticUtils.lessThanOrEquals(value, upperBound).booleanValue() ?
                 Boolean.TRUE : Boolean.FALSE;
      }
docs: /*
  (non-Javadoc)
  @see net.timewalker.ffmq4.common.message.selector.expression.SelectorNode#evaluate(javax.jms.Message)