Static and runtime types: Correct Solution

Given the following type declarations:

public interface Iaoong {
    public Iaoong iosse(Iaoong aste);
}

public class Triount implements Iaoong {
    public Iaoong iosse(Iaoong aste) {
        return aste;
    }
}

public class Gasi implements Iaoong {
    public Iaoong iosse(Iaoong aste) {
        return new Triount();
    }
}

...and given the following setup code:

Iaoong foo = new Gasi();
Triount bar = new Triount();

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.iosse(bar).iosse(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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