Prototype in PHP
Why read if you can watch?
Watch Prototype's video tutorialIn the Prototype Pattern we create one standard object for each class, and clone that object to create new instances.
In this example we have an abstract BookPrototype class, with two specific or concrete subclasses, PHPBookPrototype and SQLBookPrototype. To create a object using either PHPBookPrototype or SQLBookPrototype we call the clone method.
<?php
abstract class BookPrototype {
protected $title;
protected $topic;
abstract function __clone();
function getTitle() {
return $this->title;
}
function setTitle($titleIn) {
$this->title = $titleIn;
}
function getTopic() {
return $this->topic;
}
}
class PHPBookPrototype extends BookPrototype {
function __construct() {
$this->topic = 'PHP';
}
function __clone() {
}
}
class SQLBookPrototype extends BookPrototype {
function __construct() {
$this->topic = 'SQL';
}
function __clone() {
}
}
writeln('BEGIN TESTING PROTOTYPE PATTERN');
writeln('');
$phpProto = new PHPBookPrototype();
$sqlProto = new SQLBookPrototype();
$book1 = clone $sqlProto;
$book1->setTitle('SQL For Cats');
writeln('Book 1 topic: '.$book1->getTopic());
writeln('Book 1 title: '.$book1->getTitle());
writeln('');
$book2 = clone $phpProto;
$book2->setTitle('OReilly Learning PHP 5');
writeln('Book 2 topic: '.$book2->getTopic());
writeln('Book 2 title: '.$book2->getTitle());
writeln('');
$book3 = clone $sqlProto;
$book3->setTitle('OReilly Learning SQL');
writeln('Book 3 topic: '.$book3->getTopic());
writeln('Book 3 title: '.$book3->getTitle());
writeln('');
writeln('END TESTING PROTOTYPE PATTERN');
function writeln($line_in) {
echo $line_in."<br/>";
}
?>
BEGIN TESTING PROTOTYPE PATTERN
Book 1 topic: SQL
Book 1 title: SQL For Cats
Book 2 topic: PHP
Book 2 title: OReilly Learning PHP 5
Book 3 topic: SQL
Book 3 title: OReilly Learning SQL
END TESTING PROTOTYPE PATTERN