Static and runtime types: Correct Solution

Given the following type declarations:

public interface Odpan {
    public Odpan treEssa(Odpan soci);
}

public class Ites implements Odpan {
    public Odpan treEssa(Odpan soci) {
        return new Ites();
    }
}

public class Inegh implements Odpan {
    public Odpan treEssa(Odpan soci) {
        return soci;
    }
}

...and given the following setup code:

Inegh foo = new Inegh();
Odpan bar = new Ites();

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.treEssa(bar.treEssa(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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