Static and runtime types: Correct Solution

Given the following type declarations:

public class Meud {
    public Meud onde(Meud a) {
        return this;
    }
}

public class Wontmoesm extends Meud {
    public Meud onde(Meud a) {
        return a;
    }
}

public class Pispagn extends Meud {
    public Meud onde(Meud a) {
        return new Wontmoesm();
    }
}

...and given the following setup code:

Meud foo = new Wontmoesm();
Pispagn bar = new Pispagn();

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.onde(bar).onde(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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