Spring @Autowired not working

Question

I have some problems wth autowire annotation. My app looks like this:

Here is controller:

@Controller
public class MyController {
    @Autowired
    @Qualifier("someService")
    private SomeService someService;

    ....
}

It's a service layer:

public interface SomeService {
    ...
}

@Service
public class SomeServiceImpl implements SomeService{    
    @Autowired
    @Qualifier("myDAO")
    private MyDAO myDAO;

    ....
}

And DAO layer:

public interface MyDAO{
    ....        
}

@Repository
public class JDBCDAOImpl implements MyDAO {    
    @Autowired
    @Qualifier("dataSource")
    private DataSource dataSource;    
    ....
}

This is a app-service.xml file:

....
<bean id="propertyConfigurer"
      class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
      p:location="/WEB-INF/jdbc.properties" />

<bean id="dataSource"
      class="org.springframework.jdbc.datasource.DriverManagerDataSource"
      p:driverClassName="${jdbc.driverClassName}"
      p:url="${jdbc.url}"
      p:username="${jdbc.username}"
      p:password="${jdbc.password}"/>

<bean id="SomeService" class="com.service.SomeServiceImpl" />    
<bean id="myDAO" class="com.db.JDBCDAOImpl" />    

So... When I'm launching a web-app, MyController Autowires correctly (the someService field correctly injected by SomeServiceImpl class object), but myDAO feild of someService has null value (not injected properly).

Could you help me to find a problem?

P.S. Its interesting, but when I'm changing a "bean id" from myDAO to some another (e.g. myDAO2), system gives me an error, that injecting could not be done, because bean myDAO doesn't exist. So, Spring make an injection, but where it is? And why it's not work correctly?

Answer 1

I found the solution. As Javi said (thanks a lot for you, Javi), I have to annotate DAO and Service layer classes with @Repository and @Service annotation. Now I've tried to write like this:

@Service("someService")
public class SomeServiceImpl implements SomeService{    
    @Autowired
    @Qualifier("myDAO")
    private MyDAO myDAO;

    ....
}

and

@Repository("myDAO")
    public class JDBCDAOImpl implements MyDAO {    
    @Autowired
    @Qualifier("dataSource")
    private DataSource dataSource;    
    ....
}

and all works fine!!!

But I still not found an answer for this quesion: if application will be more complex, and will have more complex structure, where @Repositore and @Service annotation are not preferred for some classes, how to inject correctly beans, which located in lower levels (in a fields of classes, or in a field of fields of classes) (with @Autowire annotation, of course)?