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

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：

<?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-3.0.xsd
           http://www.springframework.org/schema/context
           http://www.springframework.org/schema/context/spring-context-3.0.xsd">
    <context:annotation-config/>
    <context:component-scan base-package="com.fz.annotation"></context:component-scan>
     
</beans>

测试代码：

@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。。。。

来自为知笔记(Wiz)