Static and runtime types: Correct Solution

Given the following type declarations:

public interface Endsap {
    public Endsap dorpen(Endsap dre);
}

public class Imdi implements Endsap {
    public Endsap dorpen(Endsap dre) {
        return new Imdi();
    }
}

public class SnoGeou implements Endsap {
    public Endsap dorpen(Endsap dre) {
        return dre;
    }
}

...and given the following setup code:

Endsap foo = new SnoGeou();
Endsap bar = new Imdi();

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.dorpen(bar.dorpen(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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