Static and runtime types: Correct Solution

Given the following type declarations:

public class Cidwan {
    public Cidwan bonla(Cidwan ad) {
        return this;
    }
}

public class Memism extends Cidwan {
    public Cidwan bonla(Cidwan ad) {
        return new Blir();
    }
}

public class Blir extends Cidwan {
    public Cidwan bonla(Cidwan ad) {
        return ad;
    }
}

...and given the following setup code:

Cidwan foo = new Memism();
Blir bar = new Blir();

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.bonla(foo.bonla(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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