spring03——用注解实现控制反转

之前用xml文件配置也可实现控制反转，但注解方式更为方便 1、拷贝jar包 2、创建源路径包 3、配置applicationContext.xml文件

<?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:aop="http://www.springframework.org/schema/aop"
	xmlns:p="http://www.springframework.org/schema/p" 
	xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="   
               http://www.springframework.org/schema/beans 
               http://www.springframework.org/schema/beans/spring-beans.xsd   
               http://www.springframework.org/schema/aop 
               http://www.springframework.org/schema/aop/spring-aop.xsd   
               http://www.springframework.org/schema/tx 
               http://www.springframework.org/schema/tx/spring-tx.xsd 
               http://www.springframework.org/schema/context 
               http://www.springframework.org/schema/context/spring-context.xsd">

	<context:component-scan base-package="com.huaxin.edu"/>
</beans>

4、@Component(value=“userDao”) 相当于这句话

<bean id="userDao" class="com.huaxin.edu.bean.UserDao"></bean>

这句话

@Resource(name="userDao")
private UserDao userDao;

相当于 UserDao userDao= (UserDao )applicationContext.getBean(“userDao”);

同时Dao层用@Component或@Repository Service层用@Service Servlet层用@Controller 非常方便的用法