The Struts Validator, in some form, has been available since the days of Struts 0.5. It was originally packaged as a developer contribution. Later, the core code was moved to the Jakarta Commons and a Struts-specific extension became part of Struts 1.1.
The implementation with three classes for each form,
Book, BookForm, and
BookAction, which we have used up until now, is relatively time-consuming.
DynaForms help to lift the load somewhat, but there is still plenty of work left to do, which can be especially awkward for repetitive tasks that are boring and therefore error-prone.
The Validator, ...