原型模式

定义一个复制接口,实体类去实现接口,创建实体类,使用实体类的复制方法创建新对象,可以避免new对象.避免系统开销, 也可以将原对象的属性值都继承下来.

用原型实例指定创建对象的种类,并且通过拷贝这些原型创建新的对象。

当创建新对象开销较大时，可以使用该模式，但是该模式绕过了构造函数的限制。

UML

例：

需求：

写一份简历，可以方便更新工作经历

代码实现：

简历类

import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.ObjectInputStream;import java.io.ObjectOutputStream;import java.io.Serializable;public class Resume implements Cloneable,Serializable{    /**     *      */    private static final long serialVersionUID = 5465341684135145L;    private String name;    private String age;    private String sex;    private Work work;    public Work getWork() {        return work;    }    public void setWork(Work work) {        this.work = work;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getAge() {        return age;    }    public void setAge(String age) {        this.age = age;    }    public String getSex() {        return sex;    }    public void setSex(String sex) {        this.sex = sex;    }    /**     * 浅复制     *     */    @Override    public Object clone() throws CloneNotSupportedException {        // TODO Auto-generated method stub        return super.clone();    }    /**     * 深复制     * return     * @throws Exception     */    public Object deepClone() throws Exception{          // 序列化        ByteArrayOutputStream bos = new ByteArrayOutputStream();        ObjectOutputStream oos = new ObjectOutputStream(bos);        oos.writeObject(this);        // 反序列化        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());        ObjectInputStream ois = new ObjectInputStream(bis);        return ois.readObject();    }    @Override    public String toString() {        // TODO Auto-generated method stub        System.out.println("姓名："+name+",年龄："+age+",性别:"+sex);        work.toString();        return null;    }}

工作经历类:

import java.io.Serializable;public class Work implements Serializable{    /**     *      */    private static final long serialVersionUID = 4875412545845L;    private String company;    private String timeArea;    public String getCompany() {        return company;    }    public void setCompany(String company) {        this.company = company;    }    public String getTimeArea() {        return timeArea;    }    public void setTimeArea(String timeArea) {        this.timeArea = timeArea;    }    @Override    public String toString() {        // TODO Auto-generated method stub        System.out.println("工作经历："+timeArea+"在"+company+"工作");        return super.toString();    }}

客户端

public class Client {    public static void main(String[] args) throws Exception {        Resume resumeA=new Resume();        resumeA.setAge("25");        resumeA.setName("求职者");        resumeA.setSex("男");        Work workA=new Work();        workA.setCompany("腾讯");        workA.setTimeArea("2011-2015");        resumeA.setWork(workA);        Resume resumeB= (Resume) resumeA.deepClone();        Work workB=resumeB.getWork();        workB.setTimeArea("2015-2017");        workB.setCompany("阿里巴巴");        resumeB.setWork(workB);        resumeA.toString();        resumeB.toString();    }}