spring的beans.xml的配置

 1 <?xml version="1.0" encoding="UTF-8"?>

 2 <beans xmlns="http://www.springframework.org/schema/beans"

 3        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

 4        xsi:schemaLocation="http://www.springframework.org/schema/beans

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

 6            

 7   <!--接口注入,UserDAOImpl是实现UserDAO的接口类，主要就是实现数据库的操作，根据不同的数据库类型实现不同的类操作。-->

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

 9   </bean>

10     

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

12       <!--1、set方法注入，主要用这种方法。-->

13       <property name="userDAO" ref="u" /> 

14     <!--2、构造方法注入-->

15     <!--

16        <constructor-arg> 

17            <ref bean="u"/>

18        </constructor-arg>

19      -->

20   </bean>

21 </beans>

UserDAO.java如下：

1 package com.bjsxt.dao;

2 import com.bjsxt.model.User;

3 

4 

5 public interface UserDAO {

6     public void save(User user);

7 }

UserDAOImpl.java如下：

 1 package com.bjsxt.dao.impl;

 2 import com.bjsxt.dao.UserDAO;

 3 import com.bjsxt.model.User;

 4 

 5 public class UserDAOImpl implements UserDAO {

 6     public void save(User user) {

 7         //Hibernate

 8         //JDBC

 9         //XML

10         //NetWork

11         System.out.println("user saved!");

12     }

13 }

User.java如下：

package com.bjsxt.model;



public class User {

    private String username;

    private String password;

    public String getUsername() {

        return username;

    }

    public void setUsername(String username) {

        this.username = username;

    }

    public String getPassword() {

        return password;

    }

    public void setPassword(String password) {

        this.password = password;

    }

}

UserService.java如下：

 1 package com.bjsxt.service;

 2 import com.bjsxt.dao.UserDAO;

 3 import com.bjsxt.model.User;

 4 

 5 public class UserService {

 6     private UserDAO userDAO;  

 7     /*用于beans.xml中构造方法的注入使用的；

 8     public UserService(UserDAO userDAO){

 9         this.userDAO=userDAO;

10     }

11     */

12     public void add(User user) {

13         userDAO.save(user);

14     }

15     public UserDAO getUserDAO() {

16         return userDAO;

17     }

18     public void setUserDAO(UserDAO userDAO) {

19         this.userDAO = userDAO;

20     }

21 }

那么如何来使用呢？如下代码是写在测试单元中的：
UserServiceTest.java：

 1 package com.bjsxt.service;

 2 import org.junit.Test;

 3 import org.springframework.context.ApplicationContext;

 4 import org.springframework.context.support.ClassPathXmlApplicationContext;

 5 import com.bjsxt.model.User;

 6 

 7 //Dependency Injection

 8 //Inverse of Control

 9 public class UserServiceTest {

10 

11     @Test

12     public void testAdd() throws Exception {

13         /*读取beans.xml文件ClassPathXmlApplicationContext会把读取的内容放入到bean容器中；*/

14         ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");

15         /*读取注入*/

16         UserService service = (UserService)ctx.getBean("userService");    

17         User u = new User();

18         u.setUsername("zhangsan");

19         u.setPassword("zhangsan");

20         service.add(u);

21     }

22 }