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备份与恢复
查看>>
mysql备份工具xtrabackup
查看>>
mysql备份恢复出错_尝试备份/恢复mysql数据库时出错
查看>>
mysql复制内容到一张新表
查看>>
mysql复制表结构和数据
查看>>
mysql复杂查询,优质题目
查看>>
MySQL外键约束
查看>>
MySQL多表关联on和where速度对比实测谁更快
查看>>
MySQL多表左右连接查询
查看>>
mysql大批量删除(修改)The total number of locks exceeds the lock table size 错误的解决办法
查看>>
mysql如何做到存在就更新不存就插入_MySQL 索引及优化实战(二)
查看>>
mysql如何删除数据表,被关联的数据表如何删除呢
查看>>
MySQL如何实现ACID ?
查看>>
mysql如何记录数据库响应时间
查看>>
MySQL子查询
查看>>
Mysql字段、索引操作
查看>>
mysql字段的细节(查询自定义的字段[意义-行列转置];UNION ALL;case-when)
查看>>
mysql字段类型不一致导致的索引失效
查看>>
mysql字段类型介绍
查看>>
mysql字段解析逗号分割_MySQL逗号分割字段的行列转换技巧
查看>>