{"id":9107,"date":"2020-10-05T11:00:21","date_gmt":"2020-10-05T02:00:21","guid":{"rendered":"https:\/\/www.gigas-jp.com\/appnews\/?p=9107"},"modified":"2020-10-02T19:05:55","modified_gmt":"2020-10-02T10:05:55","slug":"prototype-design-pattern","status":"publish","type":"post","link":"https:\/\/www.gigas-jp.com\/appnews\/archives\/9107","title":{"rendered":"Prototype Design Pattern"},"content":{"rendered":"\n

Prototype is a build design pattern that allows you to copy existing objects without making your code dependent on their classes.<\/p>\n\n\n\n

Declare an abstract base class that specifies a pure virtual “clone” method, and maintain a dictionary of all concrete “cloneable” derived classes. Any class that needs a “polymorphic constructor” capability: It derives from the abstract base class, registers its prototypical instance, and implements the clone () operation.<\/p>\n\n\n\n

So the client, instead of writing code that invokes the “new” operator on a wired class name, calls a “clone” operation on the abstract base class, supplying an enumerated string or data type that designates the class desired derivative. <\/p>\n\n\n\n

Lets see PHP & C# code samples as below.<\/p>\n\n\n\n

PHP<\/h3>\n\n\n\n
<?php\n\n\/\/ I made a common prototype interface for cloning purpose.\n\/\/ has a single function called _clone\nabstract class Person {\n\n    protected $name;\n\n    abstract function __clone();\n\n    function getName() {\n        return $this->name;\n    }\n    function setName($name) {\n        $this->name = $name;\n    }\n}\n\n\/\/ Here is a concrete class extending the person prototype.\n\/\/ we will implement the _clone method to support object cloning.\n\/\/This may contain a lot of fields and implementations but I will keep this simple for now.\nclass Boy extends Person {\n    function __clone() {\n\n    }\n}\n\n\n\/\/here is our first time instantiation of boy concrete class\n$person = new Boy();\n\n\/\/next time we will clone that object by using clone.\n\/\/ we will also pass the name param dynamically.\n\/\/ clone1\n$person1 = clone $person;\n$person1->setName('Hlaing');\n$person1->getName();\n\n\/\/ clone2\n$person2 = clone $boy;\n$person2->setName('Tin');\n$person2->getName();\n\nprint_r($person1);\nprint_r($person2);\n \n?>\n<\/code><\/pre>\n\n\n\n
<\/a>C#<\/h3>\n\n\n\n
using System;\nusing System.Collections.Generic;\n\nnamespace HelloWorld\n{\n    \/\/ Here is my simple object that support object cloning.\n    \/\/ I already build a function called copyclone to clone this object.\n    public class Person\n    {\n        public string Name;\n\n        public Person CopyClone()\n        {\n            return (Person)this.MemberwiseClone();\n        }\n    }\n\n    \n    class Program\n    {\n        static void Main(string[] args)\n        {\n            \/\/ firstly we build a object using new instantiation\n            Person person = new Person();\n\n            \/\/next time we will clone that object by theh function copyclone.\n            \/\/ we will also pass the name param dynamically.\n            \/\/ clone1\n            Person person1 = person.CopyClone();\n            person1.Name = \"Hlaing\";\n\n            \/\/ clone2\n            Person person2 = person.CopyClone();\n            person2.Name = \"Tin\";\n\n\n            Console.WriteLine(person1.Name);\n            Console.WriteLine(person2.Name);\n        }   \n    }\n}\n<\/code><\/pre>\n\n\n\n
By Yuuma.<\/p>\n
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