设计模式——依赖倒置原则实例(PHP实现)

<?php

/**
 * 设计模式——依赖倒置原则实例
 * Created by DannyWang
 * [e-mail]
 * 2015-05-05
 */
abstract class People {
    public abstract function eat(Fruit $fruit);//这里符合了里氏替换原则
}

abstract class Fruit {
    public abstract function getName();
}

class Danny extends People {
    public function eat(Fruit $fruit) {//这里符合了里氏替换原则
        echo 'Danny like eat ' . $fruit->getName() . '<br/>';
    }
}

class Apple extends Fruit {
    public function getName() {
        return 'Apple';
    }
}

class Banana extends Fruit {
    public function getName() {
        return 'Banana';
    }
}

//client
$me = new Danny();

$me->eat(new Apple());//这里符合了里氏替换原则
$me->eat(new Banana());//这里符合了里氏替换原则

//Danny like eat Apple
//Danny like eat Banana

?>