JPA NamedQuery : java.lang.IllegalStateException: Attempting to execute an operation on a closed EntityManager.

dao nuzdaki

@PersistenceContext
protected EntityManager entityManager;

satırını

@PersistenceContext(type=PersistenceContextType.EXTENDED)

protected EntityManager entityManager;

şeklinde deneyin.

Türkçe karakterlerin HTML karşılıkları

Ğ Ğ  Latin Capital Letter G With Breve       (Capital G Breve)
ğ ğ  Latin Small Letter G With Breve         (Small G Breve)
Ü Ü  Capital U, dieresis or umlaut mark ("Ü")
ü ü    Small u, dieresis or umlaut mark ("ü")
Ş Ş  Latin Capital Letter S With Cedilla     (Capital S Cedilla)
ş ş  Latin Small Letter S With Cedilla       (Small S Cedilla)
İ İ  Latin Capital Letter I With Dot Above   (Capital I Dot)
ı ı  Latin Small Letter Dotless I
Ö Ö    Capital O, dieresis or umlaut mark ("Ö")
ö ö    Small o, dieresis or umlaut mark ("ö")
Ç Ç    Capital C, cedilla ("Ç")
ç ç    Small c, cedilla ("ç")