<?php
/**
 * 继承拥有比组合更少的代码量
 * Created by PhpStorm.
 * User: Administrator
 * Date: 2017/6/24
 * Time: 17:29
 */

class Car
{
    public function addoil()
    {
        echo "Add oil\r\n";
    }
}

class Bmw extends Car
{

}

class Benz
{
    public $car;
    public function __construct()
    {
        $this->car = new Car();
    }
    public function addoil()
    {
        $this->car->addoil();
    }
}

$bmw = new Bmw();
$bmw->addoil();

$benz = new Benz();
$benz->addoil();