How to extend field capabilities?

[throttle]

I've extended some GXT Field classes to handle my data but i need to enhance their validation capabilities too. In particular i'd need to be able to set more than one valid range for NumberFields and more than one valid regex for a TextField.
Do i have to override the

protected boolean validateValue(String value)method in all my classes or is there an easier and/or cleanier way to do that?

Thanks in advance