PHP Factory::getFirstProduct示例

        return $this->firstProduct;
    }
    public function getSecondProduct()
    {
        if (!$this->secondProduct) {
            $this->secondProduct = new SecondProduct();
        }
        return $this->secondProduct;
    }
}
class FirstProduct implements Product
{
    public function getName()
    {
        return 'The first product';
    }
}
class SecondProduct implements Product
{
    public function getName()
    {
        return 'Second product';
    }
}
$factory = new Factory();
print_r($factory->getFirstProduct()->getName());
// The first product
print_r($factory->getSecondProduct()->getName());
// Second product
print_r($factory->getFirstProduct()->getName());
// The first product

示例#2

显示文件

文件： LazyInitialization.php 项目： rainbowzl7/design-patterns-in-php

    {
        if (!$this->firstProduct) {
            $this->firstProduct = new FirstProduct();
        }
        return $this->firstProduct;
    }
    public function getSecondProduct()
    {
        if (!$this->secondProduct) {
            $this->secondProduct = new SecondProduct();
        }
        return $this->secondProduct;
    }
}
class FirstProduct implements Product
{
    public function getName()
    {
        return 'The first Product';
    }
}
class SecondProduct implements Product
{
    public function getName()
    {
        return 'The second Product';
    }
}
$factory = new Factory();
var_dump($factory->getFirstProduct()->getName());
var_dump($factory->getSecondProduct()->getName());