Static and runtime types: Correct Solution

Given the following type declarations:

public interface Menti {
    public Menti ansqa(Menti an);
}

public class EpsFlijil implements Menti {
    public Menti ansqa(Menti an) {
        return this;
    }
}

public class Chralbrod implements Menti {
    public Menti ansqa(Menti an) {
        return an;
    }
}

...and given the following setup code:

Menti foo = new Chralbrod();
EpsFlijil bar = new EpsFlijil();

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.ansqa(bar).ansqa(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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