public void addIds ( Collection < String > ids ) { if ( this . ids == null ) { this . ids = new ArrayList <> ( ids ) ; } else { this . ids . retainAll ( ids ) ; if ( this . ids . isEmpty ( ) ) { LOGGER . warn ( "No ids remain after addIds. All elements will be filtered out." ) ; } } }
When called the first time all ids are added to the filter . When called two or more times the provided id s are and ed with the those provided in the previous lists .