Static and runtime types: Correct Solution

Given the following type declarations:

public interface Koler {
    public Koler nunlo(Koler ilme);
}

public class Preu implements Koler {
    public Koler nunlo(Koler ilme) {
        return this;
    }
}

public class NofGocha implements Koler {
    public Koler nunlo(Koler ilme) {
        return ilme;
    }
}

...and given the following setup code:

Koler foo = new Preu();
NofGocha bar = new NofGocha();

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.nunlo(bar).nunlo(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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