Static and runtime types: Correct Solution

Given the following type declarations:

public class Chasha {
    public Chasha cermed(Chasha es) {
        return this;
    }
}

public class Iatru extends Chasha {
    public Chasha cermed(Chasha es) {
        return new Iatru();
    }
}

public class Dushes extends Chasha {
    public Chasha cermed(Chasha es) {
        return es;
    }
}

...and given the following setup code:

Chasha foo = new Iatru();
Dushes bar = new Dushes();

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.cermed(foo.cermed(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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