Spring----IOC实例
第一种方式:通过getter/setter方法注入:
1、新建一个Java工程,添加spring3.1支持
2、在src下新建com.etc.dao包,新建UserDAO.java类:
package com.etc.dao;
public class UserDAO {
public void create(){
System.out.println("create");
}
}
3、在src下新建com.etc.service包,新建UserService.java类:
package com.etc.service;
import com.etc.dao.UserDAO;
public class UserService {
private UserDAO userDAO;
public void doCreate(){
userDAO.create();
}
public UserDAO getUserDAO() {
return userDAO;
}
public void setUserDAO(UserDAO userDAO) {
this.userDAO = userDAO;
}
}
4、配置applicationContext.xml文件:
<?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:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">
<bean name="userService" class="com.etc.service.UserService">
<property name="userDAO" ref="userDAO"></property>
</bean>
<!--
相当于:
UserService userService = new UserService();
UserDAO userDAO = new UserDAO();
userService.setUserDAO(userDAO);
-->
<bean name="userDAO" class="com.etc.dao.UserDAO"></bean>
</beans>
5、在工程下新建test源文件夹,在文件夹下新建com.etc.test包,在包下新建UserServiceTest.java测试类如下:
package com.etc.test;
import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.etc.service.UserService;
public class UserServiceTest {
@Test
public void test(){
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
UserService userService = (UserService) context.getBean("userService");
userService.doCreate();
}
}
第二种方式:通过构造器方式注入:
1、新建一个java工程,添加spring3.1支持
2、新建UserDAO.java类:
package com.etc.dao;
public class UserDAO {
public void create(){
System.out.println("create");
}
}
3、新建UserService.java类:
package com.etc.service;
import com.etc.dao.UserDAO;
public class UserService {
private UserDAO userDAO;
public UserService(UserDAO userDAO){
this.userDAO = userDAO;
}
public void doCreate(){
userDAO.create();
}
}
4、配置applicationContext.xml文件:
<?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:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">
<bean name="userService" class="com.etc.service.UserService">
<!-- <property name="userDAO" ref="userDAO"></property> -->
<constructor-arg index="0" ref="userDAO"></constructor-arg>
</bean>
<!--
相当于:
UserDAO userDAO = new UserDAO();
UserService userService = new UserService(userDAO);
-->
<bean name="userDAO" class="com.etc.dao.UserDAO"></bean>
</beans>
5、新建UserServiceTest.java测试类:
package com.etc.test;
import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.etc.service.UserService;
public class UserServiceTest {
@Test
public void test(){
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
UserService userService = (UserService) context.getBean("userService");
userService.doCreate();
}
}