Static and runtime types: Correct Solution

Given the following type declarations:

public interface Triaste {
    public Triaste slepec(Triaste cu);
}

public class Haczil implements Triaste {
    public Triaste slepec(Triaste cu) {
        return cu;
    }
}

public class Micant implements Triaste {
    public Triaste slepec(Triaste cu) {
        return new Micant();
    }
}

...and given the following setup code:

Triaste foo = new Micant();
Triaste bar = new Haczil();

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.slepec(foo.slepec(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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