在继承的类上重写类变量/方法

Question

I've defined a class, and I'd like to have a class method (or variable, I don't really care) which needs to be overriden by each inherited class. My best approaches have been unsuccessful:

public abstract String getHumanString(); , as abstract methods can't be static

public static String getHumanString(); , as static methods can only be hidden, not overriden.

I don't know if there is another trick I could use. I could also be happy to automatically define getHumanString() by myself on the parent class with something like humanize( class.getClass().getName() ) (I'd just make getName() look more beautiful, according to my needs), getName() is not accessible on static methods. So, to sum up, my question is:

1. Can I have a static method/variable which could be edited on subclasses?

OR, as another valid solution:

2. Can I create a static method that plays with its own class name?

Thanks in advance.

EDIT:

Imagine this situation (I'll skip useless lines, as I'm directly writing code here):

class ParentClass {
    public static (or whatever) String getHumanString() {
        return "My Parent Class";
    }

    public static showMyInfo() {
        System.out.println(getHumanString());
    }
}

class ChildClass {
    @Override
    public static (or whatever) String getHumanString() {
        return "My Child Class";
    }
}

...

public static void main()
{
   ChildClass.showMyInfo();
}

It should output (as I'd want) "My Child Class", but it actually outputs (as you all know) "My Parent Class".

Answer 1

Static methods aren't polymorphic, no. Nor are variables, by the way - you can't override variables, even instance ones. You can hide them, but not override them.

It's not really clear what you're trying to do, to be honest - but you may want to consider a corresponding type hierarchy so that the static methods become instance methods in the new types.

Answer 2

I'd like to have a readable name for each class (not just getClass().getName()), which does not depend on the object instance. In fact, I'd like to avoid instancing that class when I need getHumanString().

Have a properties file, with class name as key and human string as value. And a single static method somewhere to read it.

 static String getHumanString(Class<?> clazz){
     return humanStrings.getProperty(clazz.getName(), clazz.getSimpleName());
 }

Also lends itself to localization if necessary. Plus you can "enhance" existing classes whose definition you cannot change.

Answer 3

If this is a requirement I would suggest splitting the static members and fields into a class(es) of their own. This way your existing class can refer to a single static instance of a class which is polymorphic.