SpringAnnotation注解之@PreDestroy,@PostConstruct,@Scope
@Scope的使用很简单,直接在类上加上就行
@PostConstruct:相当于xml配置方式的init-method方法
@PreDestroy:相当于xml配置方式的destroy-method方法
例如:userService
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 | package com.fz.annotation.service; import javax.annotation.PostConstruct; import javax.annotation.PreDestroy; import javax.annotation.Resource; import org.springframework.context.annotation.Scope; import org.springframework.stereotype.Component; import com.fz.annotation.dao.UserDao; import com.fz.xml.entity.User; @Service ( "userService" ) @Scope ( "prototype" ) public class UserService { private UserDao userDao; public void userAdd(){ User user = new User(); user.setUsername( "zhangsan" ); user.setPassword( "zhangsan" ); userDao.userAdd(user); } public UserDao getUserDao() { return userDao; } @Resource (name= "userDaoImpl" ) public void setUserDao(UserDao userDao) { this .userDao = userDao; } @PostConstruct public void init(){ System.out.println( "init..." ); } @PreDestroy public void destroy(){ System.out.println( "destroy..." ); } } |
applicationContext.xml配置很简单:
1 2 3 4 5 6 7 8 9 10 11 12 | <? xml version = "1.0" encoding = "UTF-8" ?> xsi:schemaLocation="http://www.springframework.org/schema/beans < context:annotation-config /> < context:component-scan base-package = "com.fz.annotation" ></ context:component-scan > </ beans > |
测试代码:
1 2 3 4 5 6 7 8 9 | @Test public void getProperties(){ ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext( "applicationContext_annotation.xml" ); UserService userService = (UserService) ctx.getBean( "userService" ); UserService userService1 = (UserService) ctx.getBean( "userService" ); userService.userAdd(); System.out.println(userService == userService1); ctx.destroy(); } |
结果如下:
可以看出init还是执行了两次,两个对象也不是同一个对象,但是destroy同样还是不执行了。。。。