In addition to the static merging of helpsets described in Merging Helpsets, helpsets can be merged dynamically. To merge helpsets dynamically, you use the JavaHelp software API in your Java applications.
The basic API consists of the 
HelpSet.add(HelpSet) method
and its corresponding
HelpSet.remove(HelpSet)method.
These methods fire 
HelpSetEvent events for the
HelpSetListeners that have registered interest in them.
The Component UIs for the TOC, index,  search, and glossary views register for
these events and react to changes.
The semantics of merging is implemented by individual
NavigatorView objects
and
JHelpNavigator objects.
There are three basic methods:
canMerge(NavigatorView)
merge(NavigatorView)
remove(NavigatorView)
canMerge(NavigatorView) method is present in both
NavigatorView and JHelpNavigator.
The JHelpNavigator method just calls into its
corresponding NavigatorView method.
The other two methods are present only in JHelpNavigator.
 For more information about these classes and methods, refer to the JavaHelp 
  software API documentation. API information can be viewed using a web browser 
  (doc/api/overview-summary.html) or by using the sample API viewer 
  in demos\bin\apiviewer. 
 Two demonstration programs, demos\bin\merge and demos\bin\newmerge 
  are included with the JavaHelp system release. These programs demonstrate how 
  helpsets can be merged and removed dynamically. The newmerge program 
  demonstrates what happens with a UniteAppendMerge of TOCs and a SortMerge of 
  indexes. 
The sources for these programs are available under demos\src\sunw\demo\.