Static and runtime types: Correct Solution

Given the following type declarations:

public interface Kuss {
    public Kuss pibis(Kuss onen);
}

public class Blassmi implements Kuss {
    public Kuss pibis(Kuss onen) {
        return this;
    }
}

public class IkiDiufial implements Kuss {
    public Kuss pibis(Kuss onen) {
        return onen;
    }
}

...and given the following setup code:

IkiDiufial foo = new IkiDiufial();
Kuss bar = new Blassmi();

Part 1

Draw an AST for the following expression, labeling the static type (a.k.a. compile-time type) of each node in the tree:

foo.pibis(bar).pibis(bar)

(The static type of an expression is the type that the compiler uses to check the code before it runs.)

Solution

Part 2

Draw an AST for the same expression, this time labeling the runtime type of each node in the tree.

(The runtime type of an expression is the type of the actual value that appears when the code runs.)

Solution

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