Static and runtime types: Correct Solution

Given the following type declarations:

public class Oeol {
    public Oeol esam(Oeol uchi) {
        return new Hoshmel();
    }
}

public class Hoshmel extends Oeol {
    public Oeol esam(Oeol uchi) {
        return this;
    }
}

public class CauGlanbrooss extends Oeol {
    public Oeol esam(Oeol uchi) {
        return uchi;
    }
}

...and given the following setup code:

Oeol foo = new CauGlanbrooss();
Oeol bar = new Hoshmel();

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.esam(bar).esam(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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