Thanks a lot! I think the last message is what I'm trying to do: the user first chooses the type, then the user enter the value, based on the type (int, decimal, string, boolean, percent, or any other type the user could define with ranges), we will verify the validation of the value just entered.
For example:
Step1: the user chooses a type called LimiteInteger [0~1];
Step2: the user enters 2.0 in the JTextField
Step3: the user pushes the button "Accept"
Step4: Error Message poped up.
Sorry for the confusion!