spring IOC容器的关键点：
* 必须将被管理的对象定义到spring配置文件中
* 必须定义构造函数或setter方法，让spring将对象注入过来
我们可以通过下面这里例子理解spring ioc的实现。本例使用spring 4.3.10
实例:
一.导包:目前只需导个核心包
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.10.RELEASE</version>
</dependency>
二.配置spring-context.xml文件
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 http://www.springframework.org/schema/beans/spring-beans.xsd"> 5 <bean id="userDao4MySqlImpl" class="com.yztc.spring1.dao.UserDao4MySqlImpl"/> 6 <bean id="userDao40racleImpl" class="com.yztc.spring1.dao.UserDao40racleImpl"/> 7 <bean id="userManagerImpl" class="com.yztc.spring1.contrallor.UserManagerImpl"> 8 <property name="userDao" ref="userDao4MySqlImpl"/> 9 </bean> 10 11 </beans>
三.创建需要注入的类
1 public interface UserDao { 2 public void save(String username,String password); 3 }
1 package com.yztc.spring1.dao; 2 3 /** 4 * _ooOoo_ 5 * o8888888o 6 * 88" . "88 7 * (| -_- |) 8 * O = /O 9 * ___/`---'\____ 10 * . ' \| |// `. 11 * / \||| : |||// 12 * / _||||| -:- |||||- 13 * | | \ - /// | | 14 * | \_| ''---/'' | | 15 * .-\__ `-` ___/-. / 16 * ___`. .' /--.-- `. . __ 17 * ."" '< `.___\_<|>_/___.' >'"". 18 * | | : `- \`.;` _ /`;.`/ - ` : | | 19 * `-. \_ __ /__ _/ .-` / / 20 * ======`-.____`-.___\_____/___.-`____.-'====== 21 * `=---=' 22 * ............................................. 23 * 24 * @author bindu 25 * @date 2017-10-25 19:25 26 */ 27 28 29 public class UserDao4MySqlImpl implements UserDao { 30 @Override 31 public void save(String username, String password) { 32 System.out.println("----------UserDao4MySqlImpl------------"); 33 } 34 }
1 public class UserDao40racleImpl implements UserDao { 2 @Override 3 public void save(String username, String password) { 4 System.out.println("----------------UserDao40racleImpl-------------"); 5 } 6 }
四.被注入的类
1 package com.yztc.spring1.contrallor; 2 3 public interface UserManager { 4 public void save(String username,String password); 5 }
1 package com.yztc.spring1.contrallor; 2 3 import com.yztc.spring1.dao.UserDao; 4 5 /** 6 * _ooOoo_ 7 * o8888888o 8 * 88" . "88 9 * (| -_- |) 10 * O = /O 11 * ___/`---'\____ 12 * . ' \| |// `. 13 * / \||| : |||// 14 * / _||||| -:- |||||- 15 * | | \ - /// | | 16 * | \_| ''---/'' | | 17 * .-\__ `-` ___/-. / 18 * ___`. .' /--.-- `. . __ 19 * ."" '< `.___\_<|>_/___.' >'"". 20 * | | : `- \`.;` _ /`;.`/ - ` : | | 21 * `-. \_ __ /__ _/ .-` / / 22 * ======`-.____`-.___\_____/___.-`____.-'====== 23 * `=---=' 24 * ............................................. 25 * 26 * @author bindu 27 * @date 2017-10-25 19:29 28 */ 29 30 31 public class UserManagerImpl implements UserManager {
//先建立对象属性,在写构造方法或者setter方法 32 private UserDao userDao; 33 @Override 34 public void save(String username, String password) { 35 this.userDao.save(username,password); 36 } 37 38 public void setUserDao(UserDao userDao) { 39 this.userDao = userDao; 40 } 41 }
五.测试类
1 package com.yztc.spring; 2 3 import com.yztc.spring1.contrallor.UserManager; 4 import com.yztc.spring1.contrallor.UserManagerImpl; 5 import org.springframework.context.support.ClassPathXmlApplicationContext; 6 7 /** 8 * _ooOoo_ 9 * o8888888o 10 * 88" . "88 11 * (| -_- |) 12 * O = /O 13 * ___/`---'\____ 14 * . ' \| |// `. 15 * / \||| : |||// 16 * / _||||| -:- |||||- 17 * | | \ - /// | | 18 * | \_| ''---/'' | | 19 * .-\__ `-` ___/-. / 20 * ___`. .' /--.-- `. . __ 21 * ."" '< `.___\_<|>_/___.' >'"". 22 * | | : `- \`.;` _ /`;.`/ - ` : | | 23 * `-. \_ __ /__ _/ .-` / / 24 * ======`-.____`-.___\_____/___.-`____.-'====== 25 * `=---=' 26 * ............................................. 27 * 28 * @author bindu 29 * @date 2017-10-25 19:33 30 */ 31 32 33 public class SpringTest { 34 public static void main(String[] args) { 35 ClassPathXmlApplicationContext factoty = new ClassPathXmlApplicationContext("spring-context.xml"); 36 UserManager userManager = (UserManager) factoty.getBean("userManagerImpl", UserManagerImpl.class); 37 userManager.save("zhangsan","121718"); 38 } 39 }