原型模式（Prototype Pattern）是用来创建重复的对象，降低创建对象的代价。

一、需求举例：

项目中需求开发应用场景：
1.简单的项目开发由初级工程师完成；
2.高难度的项目开发由高级工程师完成。

二、类图

三、代码实例

1.工程师抽象类:Engineer

package com.lance.prototype;

public abstract class Engineer implements Cloneable {

    private String duty;

    public String getDuty() {
        return duty;
    }

    public void setDuty(String duty) {
        this.duty = duty;
    }

    private String engineerName;


    public String getEngineerName() {
        return engineerName;
    }

    public void setEngineerName(String engineerName) {
        this.engineerName = engineerName;
    }

    abstract void develop(String program);

    @Override
    public Object clone() {
        Object clone = null;
        try {
            clone = super.clone();
        } catch (CloneNotSupportedException e) {
            e.printStackTrace();
        }
        return clone;
    }

}

2. 工程师实现类：EngineerImpl

package com.lance.prototype;

public class EngineerImpl extends Engineer {

    @Override
    public void develop(String program) {
        System.out.println(this.getDuty() +":"+ this.getEngineerName() + " develop " + program);

    }
}

3.主类：PrototypePattern

package com.lance.prototype;

public class PrototypePattern {

    public static void main(String[] args) {


        System.out.println("==========start==========");

        Engineer juniorEngineer = new EngineerImpl();
        juniorEngineer.setDuty("工程师");
        juniorEngineer.setEngineerName("张三(初级)");
        juniorEngineer.develop("easy program");

        System.out.println("=======================");

        Engineer seniorEngineer = (EngineerImpl)juniorEngineer.clone();
        seniorEngineer.setEngineerName("李四(高级)");
        seniorEngineer.develop("difficult program");

        System.out.println("==========end==========");


    }
}

输出结果：

==========start==========
工程师:张三(初级) develop easy program
=======================
工程师:李四(高级) develop difficult program
==========end==========