@Autowired
	a>預設按型別by type
	b>如果想用byName,使用Qulifler
	c>寫在private field(第三種注入形式)(不建議,破封裝)
	d>如果寫在set上,@qualifier需要寫在引數上

匯入spring註解配置

xmlns:context="http://www.springframework.org/schema/context

http://www.springframework.org/schema/context

http://www.springframework.org/schema/context/spring-context.xsd">

<?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">

	<context:annotation-config />
	<bean id="userDaoImpl" class="com.bjsxd.dao.impl.UserDaoImpl">
	</bean>
	<bean id="userDaoImpl2" class="com.bjsxd.dao.impl.UserDaoImpl">
	</bean>

	<bean id="userService" class="com.bjsxd.service.UserService">
	
	</bean>
</beans>
 

package com.bjsxd.service;

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

import com.bjsxd.dao.UserDao;
import com.bjsxd.model.User;

public class UserService {
	private UserDao userDao;

	public UserDao getUserDao() {
		return userDao;
	}

	@Autowired//自動裝配
	public void setUserDao(@Qualifier("userDaoImpl")UserDao userDao) {//指定要使用的的bean的ID注入
		this.userDao = userDao;
	}

	public void add(User user) {
		userDao.save(user);
	}
}