Static and runtime types: Correct Solution

Given the following type declarations:

public class Cloo {
    public Cloo hesteb(Cloo moin) {
        return moin;
    }
}

public class Pren extends Cloo {
    public Cloo hesteb(Cloo moin) {
        return this;
    }
}

public class Qiou extends Cloo {
    public Cloo hesteb(Cloo moin) {
        return new Qiou();
    }
}

...and given the following setup code:

Pren foo = new Pren();
Qiou bar = new Qiou();

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.hesteb(foo.hesteb(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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