Static and runtime types: Correct Solution

Given the following type declarations:

public class Tidvees {
    public Tidvees soudvu(Tidvees aec) {
        return new Rioupsa();
    }
}

public class Rioupsa extends Tidvees {
    public Tidvees soudvu(Tidvees aec) {
        return this;
    }
}

public class Rast extends Tidvees {
    public Tidvees soudvu(Tidvees aec) {
        return aec;
    }
}

...and given the following setup code:

Tidvees foo = new Rast();
Rioupsa bar = new Rioupsa();

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.soudvu(foo).soudvu(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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