JPA - EntityManager.remove Examples

    private static void removeEntity(EntityManagerFactory emf, int id) {
        EntityManager em = emf.createEntityManager();
        Employee employee = em.find(Employee.class, id);
        System.out.println("-- removing entity --");
        printObject(employee);

        em.getTransaction().begin();
        em.remove(employee);
        em.getTransaction().commit();
        em.close();
    }

    private static void findAndRemoveEntity() {
        EntityManager em = entityManagerFactory.createEntityManager();
        Employee employee = em.find(Employee.class, 1);
        System.out.println("after find(): " + em.contains(employee));
        em.remove(employee);
        System.out.println("after remove(): " + em.contains(employee));
        em.close();
    }

    private static void findByReferenceAndRemoveEntity() {
        EntityManager em = entityManagerFactory.createEntityManager();
        Employee employee = em.getReference(Employee.class, 1);
        System.out.println("after getReference(): " + em.contains(employee));
        em.remove(employee);
        System.out.println("after remove(): " + em.contains(employee));
        em.close();
    }