原型模式
目的
为了避免以标准方式创建对象（如：new Foo()）带来的成本，原型模式是通过创建对象的原型并克隆它的方式来创建对象。
使用场景
- 一次性创建大量的数据（例如：在数据库中，通过 ORM 一次性创建 1,000,000 条数据）
UML 类图
代码
BookPrototype.php
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| <?php declare(strict_types = 1);
namespace DesignPatterns\Creational\Prototype;
abstract class BookPrototype
{
protected string $title;
protected string $category;
abstract public function __clone();
public function getTitle(): string
{
return $this->title;
}
public function setTitle(string $title)
{
$this->title = $title;
}
}
|
BarBookPrototype.php
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| <?php declare(strict_types = 1);
namespace DesignPatterns\Creational\Prototype;
class BarBookPrototype extends BookPrototype
{
protected string $category = 'Bar';
public function __clone()
{
}
}
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FooBookPrototype.php
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| <?php declare(strict_types = 1);
namespace DesignPatterns\Creational\Prototype;
class FooBookPrototype extends BookPrototype
{
protected string $category = 'Foo';
public function __clone()
{
}
}
|
测试
Tests/PrototypeTest.php
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| <?php declare(strict_types = 1);
namespace DesignPatterns\Creational\Prototype\Tests;
use DesignPatterns\Creational\Prototype\BarBookPrototype;
use DesignPatterns\Creational\Prototype\FooBookPrototype;
use PHPUnit\Framework\TestCase;
class PrototypeTest extends TestCase
{
public function testCanGetFooBook()
{
$fooPrototype = new FooBookPrototype();
$barPrototype = new BarBookPrototype();
for ($i = 0; $i < 10; $i++) {
$book = clone $fooPrototype;
$book->setTitle('Foo Book No ' . $i);
$this->assertInstanceOf(FooBookPrototype::class, $book);
}
for ($i = 0; $i < 5; $i++) {
$book = clone $barPrototype;
$book->setTitle('Bar Book No ' . $i);
$this->assertInstanceOf(BarBookPrototype::class, $book);
}
}
}
|
