epeatingFieldGroupFactory} and {@link CompositeField}) involves several
    wrapper classes.  For this reason, there is not one implementation per category,
    with specialized behavior in each category-implementing class.  (If it were implemented
    so, there would need to be a new subclass for each category for each distinct
    type of wrapping.)
</p><p>
    Instead, there is a main class {@link DefaultInputField} and a factory
    {@link InputFieldFactory}.  Specialized per-category properties are sto