1.Spring 的 Bean 管理:(注解方式)

1.1 创建 web 项目,引入 Spring 的开发包:

注：在 Spring 的注解的 AOP 中需要引入 spring-aop 的 jar 包。

1.2引入相关配置文件:

log4j.properties
applicationContext.xml
引入约束: 位置：spring-framework-4.2.4.RELEASE\docs\spring-framework-reference\html\xsd-configuration.html

* 引入约束:(引入 context 的约束):

<?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.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context.xsd"> 
        <!-- bean definitions here -->
        
        
	<!--spring 的 Ioc的中注解入门-->
	<!-- 使用IOC的注解开发，配置组件扫描 (那些包下的类使用IOC的注解)-->
	<context:component-scan base-package="com.rick.spring.demo1"></context:component-scan>

</beans>

1.3编写相关的类:

package com.rick.spring.demo1;

public interface UserDao {
	
	public void save();

}

package com.rick.spring.demo1;

import org.springframework.stereotype.Component;

@Component("userDao")   //相当于在XML中配置了<bean id = " userDao  "    class = "    .UserDaoImpl" /> 
public class UserDaoImpl implements UserDao {

	@Override
	public void save() {
		System.out.println("Dao中保存用户的方法执行了");
	
	}
}

package com.rick.spring.demo1;


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

/*
 * Spring的Ioc的注解开发的测试类
 */
public class SpringDemo1 {

	//传统方式
	@Test
	public void demo1() {
		UserDao userDao = new UserDaoImpl();
		userDao.save();
	}
	
	
	//spring的ioc注解方式
	@Test
	public void demo2() {
		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
		UserDao userDao = (UserDao) applicationContext.getBean("userDao");
		userDao.save();
	}
}