1.5. Prototype
1.5.1. Purpose
To avoid the cost of creating objects the standard way (new Foo()) and instead create a prototype and clone it.
1.5.2. Examples
Large amounts of data (e.g. create 1,000,000 rows in a database at once via a ORM).
1.5.3. UML Diagram
1.5.4. Code
You can also find this code on GitHub
BookPrototype.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\Prototype;
6
7abstract class BookPrototype
8{
9 protected string $title;
10 protected string $category;
11
12 abstract public function __clone();
13
14 final public function getTitle(): string
15 {
16 return $this->title;
17 }
18
19 final public function setTitle(string $title): void
20 {
21 $this->title = $title;
22 }
23}
BarBookPrototype.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\Prototype;
6
7class BarBookPrototype extends BookPrototype
8{
9 protected string $category = 'Bar';
10
11 public function __clone()
12 {
13 }
14}
FooBookPrototype.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\Prototype;
6
7class FooBookPrototype extends BookPrototype
8{
9 protected string $category = 'Foo';
10
11 public function __clone()
12 {
13 }
14}
1.5.5. Test
Tests/PrototypeTest.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\Prototype\Tests;
6
7use DesignPatterns\Creational\Prototype\BarBookPrototype;
8use DesignPatterns\Creational\Prototype\FooBookPrototype;
9use PHPUnit\Framework\TestCase;
10
11class PrototypeTest extends TestCase
12{
13 public function testCanGetFooBook()
14 {
15 $fooPrototype = new FooBookPrototype();
16 $barPrototype = new BarBookPrototype();
17
18 for ($i = 0; $i < 10; $i++) {
19 $book = clone $fooPrototype;
20 $book->setTitle('Foo Book No ' . $i);
21 $this->assertInstanceOf(FooBookPrototype::class, $book);
22 }
23
24 for ($i = 0; $i < 5; $i++) {
25 $book = clone $barPrototype;
26 $book->setTitle('Bar Book No ' . $i);
27 $this->assertInstanceOf(BarBookPrototype::class, $book);
28 }
29 }
30}