大话设计模式第十三章---建造者模式比较

<?php
class Product {
    private $_parts = array();
    public function add(string $part) {
        $this->_parts[] = $part;
    }
    public function show() {
        echo "\n PRODUCT CREATEING...<br/>";
        foreach ($this->_parts as $part) {
            echo $part;
            echo "<br/>";
        }
    }
}

abstract class Builder {
    abstract function build_part_A();
    abstract function build_part_B();
    abstract function get_result(): Product;
}

class Concrete_builder_one extends Builder {
    private $_product = null;

    public function __construct() {
        $this->_product  = new Product();
    }
    public function build_part_A() {
        $this->_product->add(‘PART A‘);
    }
    public function build_part_B() {
        $this->_product->add(‘PART B‘);
    }
    public function get_result() : Product {
        return $this->_product;
    }
}

class Concrete_builder_two extends Builder {
    private $_product = null;

    public function __construct() {
        $this->_product  = new Product();
    }
    public function build_part_A() {
        $this->_product->add(‘PART X‘);
    }
    public function build_part_B() {
        $this->_product->add(‘PART Y‘);
    }
    public function get_result() : Product {
        return $this->_product;
    }
}

class Director {
    public function concrete(Builder $builder) {
        $builder->build_part_A();
        $builder->build_part_B();
    }
}

//CLIENT CODE
$director = new Director();
$b1 = new Concrete_builder_one();
$b2 = new Concrete_builder_two();

$director->concrete($b1);
$product1 = $b1->get_result();
$product1->show();

$director->concrete($b2);
$product2 = $b2->get_result();
$product2->show();

建造者模式：

　　将一个复杂对象的构建与它的表示分离，使得同样的建造过程可以创建不同的表示。

　　如果我们用了建造者模式，那么用户就只需要指定需要建造的类型就可以得到它们，而具体建造的过程和细节就不需要知道了。

　　Director，指挥者，它是构建一个使用Builder接口的对象。在Director中完成部件的装配（即建造过程）！！