澄清在春季使用自动装配注释

Question

I am new to spring and i have been reading spring online reference as well. I have a question regarding using autowire annotation, basically i have a web application that has for example UserController.java , UserManagerService.java and UserDao.java . Please find pseudocode below:

 @Controller
   public class UserController
    {
    @autowire UserManagerService userManagerService;

    public String validateUser(String userpswrd,String username){
           return userManagerService.validateUser(userpswrd,username);
    }

    }

And the UserManagerServiceImpl:

 @Service
public class UserManagerServiceImpl{

@autowire UserDao userDao;

public String validateUser(String userpswrd,String username){
           return userDao.validateUser(userpswrd,username);
    }

I know i need to put the the following in my applicationContext.xml in order to work:

<context:component-scan base-package="com.*" />
<!-- This tells Spring to activate annotation-driven transactions -->
<tx:annotation-driven />

My question is do i need to define the UserDao and UserManagerService in the applicationContext.xml file as a bean in order for the autowire annotation UserManagerService and UserDao to work ?

Thanks in advance for the help

Answer 1

No... the component scanning will detect all @Component related beans (including `@Service, @Repository, @Controller etc.). So no you don't need to explicitly define the beans, as that would defy the need for component-scanning and automatic wiring.