This package contains the API for adding content to the help search functionality and is responsible for indexing all contents of the help system. To add content, a plug-in must extend the LuceneSearchParticipant abstract class and point to it using the org.eclipse.help.search.luceneSearchParticipant extension point.
The package also provides an abstract class that extends LuceneSearchParticipant called XMLSearchParticipant which adds functionality for parsing XML documents.