Static and runtime types: Correct Solution

Given the following type declarations:

public class Piant {
    public Piant maflol(Piant ird) {
        return this;
    }
}

public class Unsod extends Piant {
    public Piant maflol(Piant ird) {
        return ird;
    }
}

public class Goddaer extends Piant {
    public Piant maflol(Piant ird) {
        return new Goddaer();
    }
}

...and given the following setup code:

Goddaer foo = new Goddaer();
Piant bar = new Unsod();

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.maflol(foo).maflol(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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