Static and runtime types: Correct Solution

Given the following type declarations:

public interface Caokgal {
    public Caokgal phess(Caokgal usm);
}

public class Giciun implements Caokgal {
    public Caokgal phess(Caokgal usm) {
        return this;
    }
}

public class Zioheant implements Caokgal {
    public Caokgal phess(Caokgal usm) {
        return new Giciun();
    }
}

...and given the following setup code:

Caokgal foo = new Giciun();
Zioheant bar = new Zioheant();

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.phess(foo).phess(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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