Static and runtime types: Correct Solution

Given the following type declarations:

public class Iouckis {
    public Iouckis chasso(Iouckis ue) {
        return this;
    }
}

public class Ciru extends Iouckis {
    public Iouckis chasso(Iouckis ue) {
        return ue;
    }
}

public class Ecel extends Iouckis {
    public Iouckis chasso(Iouckis ue) {
        return new Ciru();
    }
}

...and given the following setup code:

Iouckis foo = new Ciru();
Iouckis bar = new Ecel();

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.chasso(bar.chasso(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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