protected HeadElement getHead ( ) { if ( this . head == null ) { Element elt = Document . get ( ) . getElementsByTagName ( "head" ) . getItem ( 0 ) ; assert elt != null : "The host HTML page does not have a <head> element" + " which is required by this injector" ; this . head = HeadElement . as ( elt ) ; } return this . head ; }
Gets the head tag element .