建造者模式

设计模式

• 抽象建造者 (interface) 接口
• 具体建造者
• 导演者
• 产品角色

模式定义

造者模式(Builder Pattern)：将一个复杂对象的构建与它的表示分离，使得同样的构建过程可以创建不同的表示。
建造者模式是一步一步创建一个复杂的对象，它允许用户只通过指定复杂对象的类型和内容就可以构建它们，用户不需要知道内部的具体构建细节。建造者模式属于对象创建型模式。根据中文翻译的不同，建造者模式又可以称为生成器模式

代码结构

实现原理

1.定义抽象建造者

<?php
/**
 * 抽象建造者(Builder)角色
 *
 * @author     Luffy (lufei@swoole.com)
 * @date       2019/9/23
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Builder;
interface Builder
{
//  public function createCar();
    //创建部件A 比如创建汽车发动机
    public function buildPartA();
    //创建部件B 比如创建汽车底盘
    public function buildPartB();
    //创建部件C 比如创建汽车变速箱
    public function buildPartC();
    // 其他的一些零件
    public function buildOthers();
    /**
     * 返回最后组装成品结果 (返回最后装配好的汽车)，
     * 成品的组装过程不在这里进行,而是转移到下面的Director类中进行，
     * 从而实现了解耦过程和部件。
     * return Product
     */
    public function getCar();
}

2.创建产品角色

<?php
/**
 * 产品(Product)角色
 *
 * @author     Luffy (lufei@swoole.com)
 * @date       2019/9/23
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Builder;
class Car
{
    /**
     * @var array
     */
    protected $_parts = [];
    public function setPartA()
    {
        $this->_parts[] = "发动机、";
        return $this;
    }
    public function setPartB()
    {
        $this->_parts[] = "底盘、";
        return $this;
    }
    public function setPartC()
    {
        $this->_parts[] = "变速箱、";
        return $this;
    }
    public function setOthers()
    {
        $this->_parts[] ="其他零件";
        return $this;
    }
    public function getCar()
    {
        $str = "这辆车由：";
        foreach ($this->_parts as $item) {
        	$str .= $item;
		}
        $str .= "组成\n";
        echo $str;
    }
}

3.实现具体建造者

<?php
/**
 * 具体建造者(CarBuilder)角色
 *
 * @author     Luffy (lufei@swoole.com)
 * @date       2019/9/23
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Builder;
class CarBuilder implements Builder
{
    protected $car;
    public function __construct()
    {
        $this->car = new Car();
    }
    public function buildPartA()
    {
        $this->car->setPartA();
    }
    public function buildPartB()
    {
        $this->car->setPartB();
    }
    public function buildPartC()
    {
        $this->car->setPartC();
    }
    public function buildOthers()
    {
        $this->car->setOthers();
    }
    public function getCar()
    {
        return $this->car;
    }
}

4.创建导演者

<?php
/**
 * 导演者(Director)角色
 *
 * @author     Luffy (lufei@swoole.com)
 * @date       2019/9/23
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Builder;
class Director
{
    private $builder;
    public function __construct(Builder $builder)
    {
        $this->builder = $builder;
    }
    public function build()
    {
        $this->builder->buildPartA();
        $this->builder->buildPartB();
        $this->builder->buildPartC();
        $this->builder->buildOthers();
        return $this->builder->getCar();
    }
}

5.客户端的通过导演者获取具体产品角色

<?php
/**
 * 建造者客户端测试文件
 *
 * @author     Luffy (lufei@swoole.com)
 * @date       2019/9/23
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
use Luffy\DesignPatterns\Builder\CarBuilder;
use Luffy\DesignPatterns\Builder\Director;
use Luffy\DesignPatterns\Builder\Car;
include __DIR__ . '/../vendor/autoload.php';
class Client
{
    public static function index()
    {
        $carBuilder = new CarBuilder();
		$director = new Director($carBuilder);
		$newCar = $director->build();
		$newCar->getCar();
    }
}
// 使用建造者
Client::index();

流式操作

<?php
/**
 * 产品(Product)角色
 *
 * @author     Luffy (lufei@swoole.com)
 * @date       2019/9/23
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
namespace Luffy\DesignPatterns\Builder;
class Car
{
    /**
     * @var array
     */
    protected $_parts = [];
    public function setPartA()
    {
        $this->_parts[] = "发动机、";
        return $this;
    }
    public function setPartB()
    {
        $this->_parts[] = "底盘、";
        return $this;
    }
    public function setPartC()
    {
        $this->_parts[] = "变速箱、";
        return $this;
    }
    public function setOthers()
    {
        $this->_parts[] ="其他零件";
        return $this;
    }
    public function getCar()
    {
        $str = "这辆车由：";
        foreach ($this->_parts as $item) {
        	$str .= $item;
		}
        $str .= "组成\n";
        echo $str;
    }
}

<?php
/**
 * 建造者客户端测试文件
 *
 * @author     Luffy (lufei@swoole.com)
 * @date       2019/9/23
 * @copyright  Swoole, Inc.
 * @package    sy-records/design-patterns
 */
use Luffy\DesignPatterns\Builder\CarBuilder;
use Luffy\DesignPatterns\Builder\Director;
use Luffy\DesignPatterns\Builder\Car;
include __DIR__ . '/../vendor/autoload.php';
class Client
{
    public static function test()
    {
        $car = new Car();
        $car->setPartA()
            ->setPartB()
            ->setPartC()
            ->setOthers()
            ->getCar();
    }
}
// 流式操作
Client::test();

参考资料:
swoole微课堂
GitHub
Graphic Design Patterns