package Ġpl . pol sl . timetable . course . filter Ċ Ċ import Ġpl . pol sl . timetable . user . User Ċ import Ġpl . pol sl . timetable . util . Invalid Id Exception Ċ Ċ interface ĠCourse Filter Service Ġ{ ĊĠĠĠ Ġ@ Throws ( Invalid Id Exception :: class ) ĊĠĠĠ Ġfun Ġcreate Filter ( user : ĠUser , Ġfilter Definition : ĠCourse Filter Definition ) ĊĊĠĠĠ Ġ@ Throws ( Invalid Id Exception :: class ) ĊĠĠĠ Ġfun Ġdelete Filter ( user : ĠUser , Ġfilter Id : ĠLong ) ĊĊĠĠĠ Ġfun Ġfilters ( user : ĠUser ): ĠList < Ident ifiable Course Filter Data > Ċ }