我不能使用静态方法，但这似乎是合理的

base class:

abstract class Challenge
{
    abstract **static** public function getName();
}

now two classes from it:

class ChallengeType1 extends Challenge
{
    public **static** function getName()
    {
        return 'Swimming';
    }
}

class ChallengeType2 extends Challenge
{
    public **static** function getName()
    {
        return 'Climbing';
    }
}

as you all might know, we can't use static, but it would be reasonable. So I can't do like that: for example, I have the classname, so I want to know it's name: ChallengeType2::getName(); - it will fail! First I should construct the object - looks unnecessary (not to mention, what it this class have very complex initialization?)

Turns out you cannot have static abstract methods on an abstract class. See here:

Why does PHP 5.2+ disallow abstract static class methods?

But you can declare an interface to require a static method.

Here is an example that compiles:

Working Example

<?php
interface IChallenge
{
    static function getName();
}

abstract class Challenge implements IChallenge
{

}

class ChallengeType1 extends Challenge
{
    public static function getName()
    {
        return 'Swimming';
    }
}

class ChallengeType2 extends Challenge
{
    public static function getName()
    {
        return 'Climbing';
    }
}