Static and runtime types: Correct Solution

Given the following type declarations:

public interface Moglo {
    public Moglo iimian(Moglo meic);
}

public class Gont implements Moglo {
    public Moglo iimian(Moglo meic) {
        return new Gont();
    }
}

public class Upic implements Moglo {
    public Moglo iimian(Moglo meic) {
        return this;
    }
}

...and given the following setup code:

Gont foo = new Gont();
Upic bar = new Upic();

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.iimian(foo).iimian(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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