question: public static Alert findByNameAndOwner ( EntityManager em , String alertName , PrincipalUser owner ) { requireArgument ( em != null , "Entity manager can not be null." ) ; requireArgument ( alertName != null && ! alertName . isEmpty ( ) , "Alert name cannot be null or empty." ) ; requireArgument ( owner != null , "Owner cannot be null." ) ; TypedQuery < Alert > query = em . createNamedQuery ( "Alert.findByNameAndOwner" , Alert . class ) ; query . setHint ( "javax.persistence.cache.storeMode" , "REFRESH" ) ; try { query . setParameter ( "name" , alertName ) ; query . setParameter ( "owner" , owner ) ; return query . getSingleResult ( ) ; } catch ( NoResultException ex ) { return null ; } }
target:  Finds an alert given its name and owner.