My name
is
Jon Skeet

Java abstract inheritance in nested classes

Does Java allow to do something similar to this:

Abstract.java:

public abstract class Abstract {
    int state;
    abstract void changeState(int newState);
    public static class Inherited extends Abstract {
        void changeState (int newState) {
            /* ... */
        }
    }
}

Base.java:

public class Base {
    static HashMap<String, Abstract> map;
    static {
        map.insert("handle", new Abstract.Inherited());
    }
}

When I try to compile it, I get: "The method insert(String, Abstract.Inherited) is undefined for the type HashMap String,Abstract". I know I can resolve it by moving Inherited completely out of Abstract, but is there a way to preserve it?

Your problem has nothing to do with nested classes, and everything to do with the fact that the method in Map is called put, not insert.

What you're trying to do is entirely valid. After changing insert to put and importing java.util.HashMap in Base.java, your code compiles.

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