package Ġde . j 4 vel in . contracts . user Ċ Ċ import Ġde . j 4 vel in . contracts . user . data . Users Repository Ċ import Ġorg . springframework . security . core . user details . UserDetails Service Ċ import Ġorg . springframework . stereotype . Service Ċ Ċ @ Service Ċ class ĠUser Auth Service ( private Ġval Ġrepository : ĠUsers Repository ) Ġ: ĠUser Details Service Ġ{ ĊĊĠĠĠ Ġoverride Ġfun Ġload User By Username ( username : ĠString ) Ġ= ĊĠĠĠĠĠĠĠ Ġrepository . findBy Username ( username ) Ġ?: Ġthrow ĠIllegalArgumentException (" No Ġsuch Ġuser : Ġ$ username ") Ċ Ċ }