Features

SimpleValidator is easily extensible: please see, [creating custom validators].

• Text will turn red (or any colour you desire) until it satisfies all the validation criteria, which you have added. This is achieved via JavafX's built in CSS style sheet support: please see the example dialog in the program's source for an example of how to adjust the relevant style sheet. ALternatively, you can just use the program to validate without any colour highlighting.
• Form textfields will adopt a Tooltip, which will report on the state of the pertinent field. i.e. whether the field is too short, too long, not a valid date etc.
• Automatic observation shut-off; whenever your gui dialogs lose focus, SimpleValidator will cease listening until focus is regained. Therefore, no CPU cycles are wasted.
• The code is tiny, and takes up little footprint.