question: public void addXPathPropertyFragment ( String name , String xpath , QName type , String eventTypeName ) { if ( ( type != XPathConstants . NODE ) && ( type != XPathConstants . NODESET ) ) { throw new IllegalArgumentException ( "XPath property for fragments requires an Node or Nodeset (XPathConstants.NODE/NODESET) return value for property '" + name + "'" ) ; } XPathPropertyDesc desc = new XPathPropertyDesc ( name , xpath , type , eventTypeName ) ; xPathProperties . put ( name , desc ) ; }
target:  Adds an event property for which the engine uses the supplied XPath expression against a DOM document node to resolve a property value.