Static and runtime types: Correct Solution

Given the following type declarations:

public interface Pelo {
    public Pelo ciscia(Pelo meb);
}

public class Chicas implements Pelo {
    public Pelo ciscia(Pelo meb) {
        return this;
    }
}

public class Acde implements Pelo {
    public Pelo ciscia(Pelo meb) {
        return new Chicas();
    }
}

...and given the following setup code:

Pelo foo = new Acde();
Pelo bar = new Chicas();

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.ciscia(foo).ciscia(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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