Static and runtime types: Correct Solution

Given the following type declarations:

public class Spiowing {
    public Spiowing iusmar(Spiowing eas) {
        return new Acguac();
    }
}

public class Slor extends Spiowing {
    public Spiowing iusmar(Spiowing eas) {
        return this;
    }
}

public class Acguac extends Spiowing {
    public Spiowing iusmar(Spiowing eas) {
        return eas;
    }
}

...and given the following setup code:

Spiowing foo = new Slor();
Acguac bar = new Acguac();

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.iusmar(bar.iusmar(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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