he
 unmarshalling process.  In 'class defined' event callbacks, application
 specific code placed in Jakarta XML Binding mapped classes is triggered during
 unmarshalling.  'External listeners' allow for centralized processing
 of unmarshal events in one callback method rather than by type event callbacks.
 <p>
 'Class defined' event callback methods allow any Jakarta XML Binding mapped class to specify 
 its own specific callback methods by defining methods with the following method signature:
 <blockquote