Scan annotator in Spring
1. Configure xml file
The code is as follows:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.2.xsd">
<!-- Classes annotated in scan package -->
base-package="Packages to scan"
<context:component-scan base-package="com.bdqn.dao,com.bdqn.service,com.bdqn.entity" />
</beans>
2. Write an annotation @ Repository("custom alias") in the implementation class of dao
The code is as follows:
package com.bdqn.dao.impl;
import org.springframework.stereotype.Repository;
import com.bdqn.dao.UserDao;
@Repository("Custom alias")
public class UserDaoImpl implements UserDao{
@Override
public int add() {
System.out.println("Added successfully!");
return 1;
}
}
3. Add the annotation @ Service("custom alias") to the service implementation class
The code is as follows:
package com.bdqn.service.impl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Service;
import com.bdqn.dao.UserDao;
import com.bdqn.service.UserService;
@Service("Custom alias")
public class UserServiceImpl implements UserService{}
4. Add annotation to the method in the service implementation class
@Autowired: automatic assembly;
@Qualifier (custom alias): find the custom alias of the assembly object – associate the custom alias in the dao implementation layer.
5. Test code:
ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");
UserService impl=(UserService) applicationContext.getBean("userService");---userService by@Service("Custom alias")Custom alias in
impl.add();