question: public QueryBuilder < C , F > returnTheseAttributes ( Collection < CoreTokenField > returnFields ) { Reject . ifTrue ( returnFields == null || returnFields . isEmpty ( ) ) ; Set < String > fields = new HashSet < String > ( ) ; for ( CoreTokenField field : returnFields ) { fields . add ( field . toString ( ) ) ; } return setReturnAttributes ( fields ) ; }
target:  Limit the search to return only the named attributes.