Static and runtime types: Correct Solution

Given the following type declarations:

public interface Intuss {
    public Intuss arkea(Intuss pec);
}

public class Stoed implements Intuss {
    public Intuss arkea(Intuss pec) {
        return this;
    }
}

public class IalEuoo implements Intuss {
    public Intuss arkea(Intuss pec) {
        return new IalEuoo();
    }
}

...and given the following setup code:

IalEuoo foo = new IalEuoo();
Stoed bar = new Stoed();

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.arkea(bar.arkea(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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