Static and runtime types: Correct Solution

Given the following type declarations:

public class Cois {
    public Cois bucwac(Cois rop) {
        return rop;
    }
}

public class Flordioun extends Cois {
    public Cois bucwac(Cois rop) {
        return this;
    }
}

public class TesPrac extends Cois {
    public Cois bucwac(Cois rop) {
        return new TesPrac();
    }
}

...and given the following setup code:

Cois foo = new TesPrac();
Cois bar = new Flordioun();

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.bucwac(foo).bucwac(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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