question: public void addAllowed ( Class < ? > c , String displayName ) { HashSet < String > list ; list = m_Allowed . get ( c ) ; if ( list == null ) { list = new HashSet < String > ( ) ; m_Allowed . put ( c , list ) ; } list . add ( displayName ) ; }
target:  adds the given property (display name) to the list of allowed properties for the specified class.