@@ -0,0 +1,427 @@
+package dhbw.verteiltesysteme.quizduell.server.model;%0A%0Aimport javax.persistence.EntityManager;%0Aimport javax.persistence.EntityManagerFactory;%0Aimport javax.persistence.Persistence;%0A%0Apublic enum Database %7B%0A    ENTITY_MANAGER(Persistence.createEntityManagerFactory(%22emf%22));%0A%0A    private EntityManager entityManager;%0A%0A    Database(EntityManagerFactory factory) %7B%0A        this.entityManager = factory.createEntityManager();%0A    %7D%0A%7D%0A

Add singleton for entity manager