public interface AbstractDAO<Id, Entity> {
    Entity getById(Id id);

    List<Entity> getAll();

    void save(Entity entity);

    void update(Entity entity);

    void delete(Entity entity);

    void deleteById(Id id);
}

abstract class HibernateBasedDAO<Id, Entity> implements AbstractDAO<Id, Entity> {
    @Autowired
    SessionFactory sessionFactory;

    @Override public void delete(Entity entity) {
        Session session = sessionFactory.openSession();

        Transaction transaction = session.beginTransaction();

        session.delete(entity);

        transaction.commit();

        session.close();
    }

    @Override public void save(Entity entity) {
        Session session = sessionFactory.openSession();

        Transaction transaction = session.beginTransaction();

        session.save(entity);

        transaction.commit();

        session.close();
    }

    @Override public void update(Entity entity) {
        Session session = sessionFactory.openSession();

        Transaction transaction = session.beginTransaction();

        session.update(entity);

        transaction.commit();

        session.close();
    }

    @Override public void deleteById(Id id) {
        Session session = sessionFactory.openSession();

        Transaction transaction = session.beginTransaction();

        /* session.delete(session.get(Entity.class, id)) - не работает, но как исправить не знаю пока. */

        transaction.commit();

        session.close();

    }

    @Override
    public Entity getById(Id id) {
        throw new UnsupportedOperationException();
    }

    @Override
    public List<Entity> getAll() {
        return null;  //To change body of implemented methods use File | Settings | File Templates.
    }
}

public interface AbstractDAO<Id, Entity> {
    Entity getById(Id id);

    List<Entity> getAll();

    void save(Entity entity);

    void update(Entity entity);

    void delete(Entity entity);

    void deleteById(Id id);
}

interface UserDAO extends AbstractDAO<Integer, User> {
}

@Repository
class HibernateBasedUserDAOImpl implements UserDAO {
    @Autowired
    private SessionFactory sessionFactory;

    @Override public void delete(User user) {
        sessionFactory.getCurrentSession().delete(user);
    }

    @Override public User getById(Integer id) {
        return (User) sessionFactory.getCurrentSession().get(User.class, id);
    }

    @Override public List<User> getAll() {
        return (List<User>) sessionFactory.getCurrentSession().createCriteria(User.class).list();
    }

    @Override public void save(User user) {
        sessionFactory.getCurrentSession().save(user);
    }

    @Override public void update(User user) {
        sessionFactory.getCurrentSession().update(user);
    }

    @Override public void deleteById(Integer id) {
        sessionFactory.getCurrentSession().delete(getById(id));
    }
}

@Repository
public class UserDAOImpl extends HibernateBasedDAO implements UserDAO {
    @Transactional
    @Override public User getById(Integer id) {
        return (User) getCurrentSession().get(User.class, id);
    }

    @Transactional
    @Override public List<User> getAll() {
        return (List<User>) getCurrentSession().createCriteria(User.class).list();
    }

    @Transactional
    @Override public void save(User user) {
        getCurrentSession().save(user);
    }

    @Transactional
    @Override public void update(User user) {
        getCurrentSession().update(user);
    }

    @Transactional
    @Override public void delete(User user) {
        getCurrentSession().delete(user);
    }

    @Transactional
    @Override public void deleteById(Integer id) {
        delete(getById(id));
    }
}

    <bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory" />
    </bean>

    <tx:annotation-driven transaction-manager="txManager"/>

    <tx:advice id="txAdvice" transaction-manager="txManager">
        <tx:attributes>
            <tx:method name="get*" read-only="true"/>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

@Transactional
public void f() {
    User u1 = new User();
    /* ... */

    save(u1);

    save(u2);

    throw new RuntimeException();
}