One interface, one class: multiple beans

[alan.lohse]

Excuse me if there is already a topic about this but I could not find.

I was using spring 2.5 configured by xml and I'm migrating to annotation.

I have a interface DAO where I defined some methods for database access.

And I have a unique implementation called GenericJpaDAOImpl. This implementation have some features that reduce the needing of writing queries, but I need to tell it which entity it is working.

That was my previous configuration:

<bean id="productDAO" class="com.xxx.dao.impl.GenericJpaDAOImpl">
    <constructor-arg value="com.xxx.entities.Product" />
</bean>

<bean id="userDAO" class="com.xxx.dao.impl.GenericJpaDAOImpl">
    <constructor-arg value="com.xxx.entities.User" />
</bean>

public class RequestCaseService {
    private DAO<Product, Long> productDAO;
    private DAO<User, Long> userDAO;

    public void setProductDAO(DAO<Product, Long> productDAO) {
        this.productDAO = productDAO;
    }
   
    public void setUserDAO(DAO<User, Long> userDAO) {
        this.userDAO= userDAO;
    }
   
}

I found a solution, but it's not a good and productive solution and I consider it a makeshift solution.

@Repository("dao")
@Scope("prototype")
public class GenericJpaDAOImpl<E,ID> implements DAO<E,ID> {
    // ...
}

@Service
public class RequestCaseService {
    private DAO<Product, Long> productDAO;
    private DAO<User, Long> userDAO;

    @Autowired
    public void setProductDAO(DAO<Product, Long> productDAO) {
        productDAO.setEntityClass(Product.class);
        this.productDAO = productDAO;
    }
   
    @Autowired
    public void setUserDAO(DAO<User, Long> userDAO) {
        userDAO.setEntityClass(User.class);
        this.userDAO= userDAO;
    }
   
}

I thank you if there is a definitive solution.

[alan.lohse]

anyone can tell me something?

[gmateo]

Hi,
In your case maybe the best option is to configure your: "productDAO" and "userDAO" in xml and only doing el autowiring with annotations.

It means that you mantain:

<bean id="productDAO" class="com.xxx.dao.impl.GenericJpaDAOImpl">
<constructor-arg value="com.xxx.entities.Product" />
</bean>

<bean id="userDAO" class="com.xxx.dao.impl.GenericJpaDAOImpl">
<constructor-arg value="com.xxx.entities.User" />
</bean>

and in the service do the autowiring:

@Service
public class RequestCaseService {
@Autowired
@Qualifier("productDAO")
private DAO<Product, Long> productDAO;
@Autowired
@Qualifier("userDAO")
private DAO<User, Long> userDAO;

With these option your settings in the service are not needed.

Regards