Static and runtime types: Correct Solution

Given the following type declarations:

public class Brirco {
    public Brirco giuEnha(Brirco nes) {
        return this;
    }
}

public class Afas extends Brirco {
    public Brirco giuEnha(Brirco nes) {
        return nes;
    }
}

public class TreOoldsha extends Brirco {
    public Brirco giuEnha(Brirco nes) {
        return new Afas();
    }
}

...and given the following setup code:

Brirco foo = new Afas();
TreOoldsha bar = new TreOoldsha();

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.giuEnha(foo.giuEnha(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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