<?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-2.5.xsd

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

           http://www.springframework.org/schema/context/spring-context-2.5.xsd">

    <context:annotation-config />                          //相当于初始化了四个bean 确保能够识别出annotation

  <bean id="u" class="com.bjsxt.dao.impl.UserDAOImpl">

  </bean>

  <bean id="u2" class="com.bjsxt.dao.impl.UserDAOImpl">

  </bean>

  <bean id="userService" class="com.bjsxt.service.UserService" >

  </bean>

</beans>

package com.bjsxt.service;

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

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

import com.bjsxt.dao.UserDAO;

import com.bjsxt.model.User;

public class UserService {

    private UserDAO userDAO;  

    public void init() {

        System.out.println("init");

    }

    public void add(User user) {

        userDAO.save(user);

    }

    public UserDAO getUserDAO() {

        return userDAO;

    }

    @Autowired                                                                                //使用anotation

    public void setUserDAO(@Qualifier("u") UserDAO userDAO) {                               //制定具体注入哪一个

        this.userDAO = userDAO;

    }

    public void destroy() {

        System.out.println("destroy");

    }

}