Static and runtime types: Correct Solution

Given the following type declarations:

public class Breght {
    public Breght spati(Breght e) {
        return e;
    }
}

public class Hondpang extends Breght {
    public Breght spati(Breght e) {
        return this;
    }
}

public class Cosshar extends Breght {
    public Breght spati(Breght e) {
        return new Cosshar();
    }
}

...and given the following setup code:

Breght foo = new Hondpang();
Cosshar bar = new Cosshar();

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.spati(bar.spati(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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