Inheritance, abstract and concrete

Question

Given:
*abstract public class Foo {
* protected static int bat;
* public static int bat() {
* return bat;
*public class Bar extends Foo {
* private static int bat = 5;
Assuming that you have complete rewrite power over both classes, is there any way to have a situation where:
* Foo f = new Bar();
* int x = f.bat();
will set x == 5 without putting an identical
* public static int bat() {
* return bat;
in every single class that extends Foo?

Answer 1

It's a complicated situation. I have a large number
of user-defined classes that are all being stored
together. I want to be able to pass them to the same
functions, so I don't have to rewrite the functions a
dozen times with only the variable class changing, so
I defined them all as extensions of one abstract
class, but I also need to be able to tell them apart
when I need to handle them differently. It seemed to
me that the best way to do that was by giving each
different concrete class a distinct id number, that
the handler can use in the rare cases when it's
needed. I thought the id should be declared static
because it belongs to the class, not to individual
instances of the class. But I want to keep it
private, so nobody can mess with it, so I also need a
public function to return it. And since it works
with a static value, it has to be declared as a
static function.This sounds wrong.
If they are user defined classes then it is not possible for you to tell them apart.
Or your terminology means something different.
If you are writing a plug in engine where something is added later, then the engine can no rely on anything specific about the plug ins. If it does, they are not plug ins.
If you need to handle them differently with some common categories of functionality then you should be using interfaces and helper classes.
Pseudo code would be like this...
      interface CommonStuff
            String getName();
     interface Communications
           boolean sendInfo();
     interface Storage
           boolean storeIt();
    class PlugInEngine
         void process(Object o)
                if (o instanceof Communications)
                      ((Communications)o).sendInfo();
                if (o instanceof Storage)
                      ((Communications)o).storeIt();
                if (o instanceof CommonStuff)
                      log("Finished name=" + ((CommonStuff)o).getName());
    }