php面向对象 final关键字

//final修饰的类无法被子类继承 
final class human{
  
}

class man extends human{
  
}

$m = new man();
//Fatal error: Class man may not inherit from final class (human)


// final修饰的方法无法重写父类的方法
class human{
  final function eat(){
    echo __METHOD__;  
  }
}

class man extends human{
  function eat(){
    echo __METHOD__;; 
  }
}

$m = new man();
$m->eat();
// atal error: Cannot override final method human::eat()