Prototype Pattern

Prototype Pattern Copy and use the instance

On this page ・ Confirmation of Prototype Pattern -Store and use the instance in the Map collection I will describe about

Design Pattarm MENU

Confirmation of Prototype Pattern

Check with the following class structure

class	Explanation
samPrototype.class	Have a method to make a copy of yourself
user(Main.class)	Check the operation

User Includes the meaning that other developers use this pattern

If you use the clone () method, implement the java.lang.Cloneable interface

Let's check

`samPrototype.class`


class samPrototype implements Cloneable{         // java.lang.Implement Cloneable
  void todo(){System.out.println("prototype");}
  
  samPrototype getClone(){
    samPrototype pro = null;
    try{pro=(samPrototype) clone();              // clone()And make a copy of itself
    }catch(Exception e){}
    return pro;
  }
}

`user(Main.class)`


public static void main(String[] args){
  samPrototype pr = new samPrototype();
  pr.getClone().todo();
}}

Store and use instances in the Map collection

For Prototype Pattern, register multiple instances in advance There is a usage to execute clone () if necessary

Implement with the following configuration

name of the class	Explanation
prototype.interface	Implement Cloneable and clone()Define a method
prototypeImple.class	prototype.Implement interface and clone()Implement the method
prototypeManager.class	Keep a class instance that implements prototype in a collection clone in prototype type()Issue an instance using a method
user(Main.class)	Check the operation

Let's make a class

`prototype.interface`


interface prototype extends Cloneable{
  void todo();
  prototype exeClone();
}

`prototypeImple.class`


class prototypeImple implements prototype{
  String name;
  prototypeImple(String name){this.name=name;}

  public void todo(){System.out.println(name);}

  public prototype exeClone(){
      prototype pro = null;
      try{pro = (prototype) clone();}catch(Exception e){}
      return pro;
  }
}

`usr(Main.class)`


public static void main(String[] args){
  prototypeManager pm = new prototypeManager();
  pm.set(0, new prototypeImple("A"));
  pm.set(1, new prototypeImple("B"));
  prototype p1 = pm.getClone(0);
  prototype p2 = pm.getClone(1);
  p1.todo();
  p2.todo();
}}