spring generics

Spring 4.0 can inject subclass generic types for subclasses, reference to member variables
BaseService<T>: There are two subclasses of RoleService and UserService
BaseRepepositry<T>: There are two subclasses of UserRepository and RoleRepositry

because BaseService<T> inherits BaseRepepositry<T> , it is concluded that the following subclasses also have such a relationship
Code :
User.java

public class User {

}

BaseService.java

import org.springframework.beans.factory.annotation.Autowired;

public class BaseService<T> {
	 @Autowired
	 protected BaseRepository<T> repository;
	 
	 public void add(){
		 
		 System.out.println("adding....");
		 System.out.println(repository);	 
	 }
}

UserService.java

import org.springframework.stereotype.Repository;

@Repository
public class UserService extends BaseService<User>{

}

BaseRepository.java

public class BaseRepository<T> {}

UserRepository.java

import org.springframework.stereotype.Repository;
 @Repository //Hand over to the IOC container to manage
public class UserRepository extends BaseRepository<User>{}

Main.java

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {

    public static void main(String[] args) {
         ApplicationContext applicationContext = new ClassPathXmlApplicationContext(
                 "applicationContext.xml");
 
        UserService userService = (UserService) applicationContext.getBean("userService");
 
        userService.add();
    
     }
}

Output result:

adding....
com.spring.txing.UserRepository@7174d93a

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