Static and runtime types: Correct Solution

Given the following type declarations:

public interface Deurbuac {
    public Deurbuac rantdi(Deurbuac taee);
}

public class Dooe implements Deurbuac {
    public Deurbuac rantdi(Deurbuac taee) {
        return new Onio();
    }
}

public class Onio implements Deurbuac {
    public Deurbuac rantdi(Deurbuac taee) {
        return taee;
    }
}

...and given the following setup code:

Deurbuac foo = new Dooe();
Onio bar = new Onio();

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.rantdi(bar.rantdi(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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