结构型--享元模式

设计模式

• 享元抽象类
• 共享的具体享元类
• 不共享的具体享元类
• 享元工厂

享元抽象类

<?php
/**
 * Flyweight.php
 *
 * @author     Luffy <lufei@swoole.com>
 * @date       2019/12/9
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Flyweight;
abstract class Flyweight
{
    /**
     * @var
     */
    protected $name;
    /**
     * Flyweight constructor.
     * @param $name
     */
    public function __construct($name)
    {
        $this->name = $name;
    }
    /**
     * @param $content
     */
    abstract public function get($content);
}

共享的具体享元类

<?php
/**
 * ConcreteFlyweight.php
 *
 * @author     Luffy <lufei@swoole.com>
 * @date       2019/12/9
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Flyweight;
class ConcreteFlyweight extends Flyweight
{
    /**
     * @param $content
     */
    public function get($content)
    {
        echo "共享的：{$content} {$this->name}\n";
    }
}

不共享的具体享元类

<?php
/**
 * UnsharedConcreteFlyweight.php
 *
 * @author     Luffy <lufei@swoole.com>
 * @date       2019/12/9
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Flyweight;
class UnsharedConcreteFlyweight extends Flyweight
{
    /**
     * @param $content
     */
    public function get($content)
    {
        echo "不共享的：{$content} {$this->name}\n";
    }
    public function del()
    {
        $this->name = '';
    }
}

享元工厂

<?php
/**
 * FlyweightFactory.php
 *
 * @author     Luffy <lufei@swoole.com>
 * @date       2019/12/9
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Flyweight;
class FlyweightFactory
{
    /**
     * @var array
     */
    private $flyweights = [];
    /**
     * @param $name
     * @return mixed
     */
    public function getFlyweight($name)
    {
        if (!isset($this->flyweights[$name])) {
            $this->flyweights[$name] = new ConcreteFlyweight($name);
        }
        return $this->flyweights[$name];
    }
}

客户端调用

<?php
/**
 * Client.php
 *
 * @author     Luffy <lufei@swoole.com>
 * @date       2019/12/9
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Flyweight;
include __DIR__ . '/../vendor/autoload.php';
class Client
{
    public static function run()
    {
        $flyweight = new FlyweightFactory();
        $obj1 = $flyweight->getFlyweight("⭐️");
        $obj1->get('第1个');
        $obj2 = $flyweight->getFlyweight("⭐️");
        $obj2->get('第50个');
        var_dump($obj1 === $obj2);
        $obj3 = $flyweight->getFlyweight("🍎");
        $obj3->get('第1个');
        // 不共享的
        $obj4 = new UnsharedConcreteFlyweight("🍍");
        $obj4->get("一");
        $obj4->del();
        $obj4->get("一");
    }
}
Client::run();

参考资料:
swoole微课堂
示例代码