博客
关于我
GoF23 原型模式学习笔记
阅读量:285 次
发布时间:2019-03-03

本文共 2518 字,大约阅读时间需要 8 分钟。

GoF23 原型模式学习笔记

1. 实现Cloneable接口 2. 重写clone方法
应用场景: 1. Spring Bean 的创建:单例模式、原型模式 2. 与工厂模式一起使用,代替 new

浅拷贝

代码中表现为cloneVideo的publishTime只是指向了原video的publishTime
package prototype.shallow;import java.util.Date;public class Video implements Cloneable {   	private String name;	private Date publishTime;	public Video(String name, Date publishTime) {   		this.name = name;		this.publishTime = publishTime;	}	public Video() {   	}	public String getName() {   		return name;	}	public void setName(String name) {   		this.name = name;	}	public Date getPublishTime() {   		return publishTime;	}	public void setPublishTime(Date publishTime) {   		this.publishTime = publishTime;	}	@Override	protected Object clone() throws CloneNotSupportedException {   		return super.clone();	}	@Override	public String toString() {   		return "Video [name=" + name + ", publishTime=" + publishTime + "]";	}}
package prototype.shallow;import java.util.Date;public class Main {   	public static void main(String[] args) throws CloneNotSupportedException {   		Date date = new Date();		Video video = new Video("VideoName", date);		Video cloneVideo = (Video)video.clone();		System.out.println(video);		System.out.println(cloneVideo);				date.setTime(1231241);				System.out.println(video);		System.out.println(cloneVideo);	}}

在这里插入图片描述

深拷贝

package prototype.deep;import java.util.Date;public class Video implements Cloneable {   	private String name;	private Date publishTime;	public Video(String name, Date publishTime) {   		this.name = name;		this.publishTime = publishTime;	}	public Video() {   	}	public String getName() {   		return name;	}	public void setName(String name) {   		this.name = name;	}	public Date getPublishTime() {   		return publishTime;	}	public void setPublishTime(Date publishTime) {   		this.publishTime = publishTime;	}	@Override	protected Object clone() throws CloneNotSupportedException {   		Object obj = super.clone();		Video v = (Video)obj;		v.publishTime = (Date)this.publishTime.clone();		return obj;	}	@Override	public String toString() {   		return "Video [name=" + name + ", publishTime=" + publishTime + "]";	}}
package prototype.deep;import java.util.Date;public class Main {   	public static void main(String[] args) throws CloneNotSupportedException {   		Date date = new Date();		Video video = new Video("VideoName", date);		Video cloneVideo = (Video)video.clone();		System.out.println(video);		System.out.println(cloneVideo);				date.setTime(1231241);				System.out.println(video);		System.out.println(cloneVideo);	}}

在这里插入图片描述

转载地址:http://wssl.baihongyu.com/

你可能感兴趣的文章
mysql 修改默认字符集为utf8
查看>>
Mysql 共享锁
查看>>
mysql 写入慢优化
查看>>
mysql 创建表,不能包含关键字values 以及 表id自增问题
查看>>
mysql 判断表字段是否存在,然后修改
查看>>
MySQL 多表联合查询:UNION 和 JOIN 分析
查看>>
MySQL 大数据量快速插入方法和语句优化
查看>>
mysql 如何给SQL添加索引
查看>>
mysql 字段区分大小写
查看>>
mysql 字段类型类型
查看>>
MySQL 存储引擎
查看>>
mysql 更新子表_mysql 在update中实现子查询的方式
查看>>
mysql 自增id和UUID做主键性能分析,及最优方案
查看>>
Mysql 自定义函数
查看>>
mysql 行转列 列转行
查看>>
Mysql 表分区
查看>>
mysql 表的操作
查看>>
MySQL 触发器
查看>>
mysql 让所有IP访问数据库
查看>>
mysql 记录的增删改查
查看>>