在这段代码中，最好是使用抽象类代替接口，还是现在好呢？如果是这样，为什么？
/** contract for all flyable vehicles **/
interface iFlyable {
public function fly();
}
/* concrete implementations of iFlyable interface */
class JumboJet implements iFlyable {
public function fly() {
return "Flying 747!";
}
}
class FighterJet implements iFlyable {
public function fly() {
return "Flying an F22!";
}
}
class PrivateJet implements iFlyable {
public function fly() {
return "Flying a Lear Jet!";
}
}
/** contract for conrete Factory **/
/**
* "Define an interface for creating an object, but let the classes that implement the interface
* decide which class to instantiate. The Factory method lets a class defer instantiation to
* subclasses."
**/
interface iFlyableFactory {
public static function create( $flyableVehicle );
}
/** concrete factory **/
class JetFactory implements iFlyableFactory {
/* list of available products that this specific factory makes */
private static $products = array( 'JumboJet', 'FighterJet', 'PrivateJet' );
public static function create( $flyableVehicle ) {
if( in_array( $flyableVehicle, JetFactory::$products ) ) {
return new $flyableVehicle;
} else {
throw new Exception( 'Jet not found' );
}
}
}
$militaryJet = JetFactory::create( 'FighterJet' );
$privateJet = JetFactory::create( 'PrivateJet' );
$commercialJet = JetFactory::create( 'JumboJet' );
界面更加灵活。这样，并不是所有苍蝇都被强制从同一个基类继承（php不支持多重继承）
所以
class bird extends animal implements flyable
class plane extends machine implements flyable
class cloud implements flyable
有时并不需要灵活性。
如果多个飞行类需要相同的fly（）方法，则抽象类还可以提供函数定义，从而减少代码重复
希望能帮助您了解您的选择
本文收集自互联网，转载请注明来源。
如有侵权，请联系 [email protected] 删除。
我来说两句