1.8. Static Factory
1.8.1. Doel
Net als bij AbstractFactory, wordt dit patroon gebruikt om series van gerelateerde of afhankelijke objecten te maken. Het verschil tussen dit en het abstracte fabriekspatroon is dat het statische fabriekspatroon slechts één statische methode gebruikt om alle soorten objecten te maken die het kan maken. Het wordt meestal ‘fabriek’ of ‘bouwen’ genoemd.
1.8.2. UML Diagram
1.8.3. Code
Je kan deze broncode terugvinden op GitHub
StaticFactory.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\StaticFactory;
6
7use InvalidArgumentException;
8
9/**
10 * Note1: Remember, static means global state which is evil because it can't be mocked for tests
11 * Note2: Cannot be subclassed or mock-upped or have multiple different instances.
12 */
13final class StaticFactory
14{
15 public static function factory(string $type): Formatter
16 {
17 return match ($type) {
18 'number' => new FormatNumber(),
19 'string' => new FormatString(),
20 default => throw new InvalidArgumentException('Unknown format given'),
21 };
22 }
23}
Formatter.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\StaticFactory;
6
7interface Formatter
8{
9 public function format(string $input): string;
10}
FormatString.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\StaticFactory;
6
7class FormatString implements Formatter
8{
9 public function format(string $input): string
10 {
11 return $input;
12 }
13}
FormatNumber.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\StaticFactory;
6
7class FormatNumber implements Formatter
8{
9 public function format(string $input): string
10 {
11 return number_format((int) $input);
12 }
13}
1.8.4. Теst
Tests/StaticFactoryTest.php
1<?php
2
3declare(strict_types=1);
4
5namespace DesignPatterns\Creational\StaticFactory\Tests;
6
7use InvalidArgumentException;
8use DesignPatterns\Creational\StaticFactory\FormatNumber;
9use DesignPatterns\Creational\StaticFactory\FormatString;
10use DesignPatterns\Creational\StaticFactory\StaticFactory;
11use PHPUnit\Framework\TestCase;
12
13class StaticFactoryTest extends TestCase
14{
15 public function testCanCreateNumberFormatter()
16 {
17 $this->assertInstanceOf(FormatNumber::class, StaticFactory::factory('number'));
18 }
19
20 public function testCanCreateStringFormatter()
21 {
22 $this->assertInstanceOf(FormatString::class, StaticFactory::factory('string'));
23 }
24
25 public function testException()
26 {
27 $this->expectException(InvalidArgumentException::class);
28
29 StaticFactory::factory('object');
30 }
31}