Javadoc
Interface only used by Woodstox core. The main reason for the interface
is to reduce coupling with the input element stack and dtd validator
instances: while dtd validator needs to be able to inject namespace
declarations based on attribute default values, it should not have to
know too much about element stack implementation, and vice versa.
As a result, this interface defines API input element stack calls
on the dtd validator instance. Validator instance then refers to the
input element stack base class to do callbacks if and as necessary.