Sping5学习（六）：IOC操作Bean管理 之 完全注解开发

package demo02.config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration  //作为配置类，替代xml配置文件
@ComponentScan(basePackages = {"demo02"})
public class SpringConfig {
}

package demo02;
import demo02.dao.UserDao;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Component;
@Component
public class UserService {
    //在service里面注入dao属性
    @Autowired      //根据类型注入，但一个实现类中可能有多个类型，
                    // service并不知道要找哪一个，因此需要配合@Qualifier根据名称查找
    @Qualifier(value = "userDaoImpl")
    private UserDao userDao;
    public void add(){
        System.out.println("hahaha");
        userDao.add();
    }
}

@Test
    public void testService2(){
        ApplicationContext context = new AnnotationConfigApplicationContext(SpringConfig.class);
        UserService userService = context.getBean("userService", UserService.class);
        System.out.println(userService);
        userService.add();
    }