public abstract class AbstractDao<T> {

    private Class<T> entityClass;

    public AbstractDao(Class<T> entityClass) {
        this.entityClass = entityClass;
    }

    protected abstract EntityManager getEntityManager();

    public void create(T entity) {
        getEntityManager().persist(entity);
    }

    public void save(T entity) {
        getEntityManager().merge(entity);
    }

    public void remove(T entity) {
        getEntityManager().remove(getEntityManager().merge(entity));
    }
	
    public T find(Object id) {
        return getEntityManager().find(entityClass, id);
    }
	
    public List<T> findAll() {
        Query q = getEntityManager().createQuery("from " + entityClass.getSimpleName());
        return q.getResultList();
    }
}