Supports event changes in JavaHelp classes. `HelpModelEvent` and `HelpModelListener` support changes to the locations within HelpSets being presented, `TextHelpModelEvent` and `TextHelpModelListener` support textual changes and `HelpSetEvent`, and `HelpSetListener` support changes to the HelpSet itself.

`EventListenerList` is used as a convenience class to maintain lists of listeners and it is functionally equivalent to the equivalent Swing class--it is included to avoid adding unwanted dependencies on Swing.

## Related Documentation

For overviews, tutorials, examples, guides, tool support, and other documentation, please see the JavaHelp System User's Guide.