Static and runtime types: Correct Solution

Given the following type declarations:

public interface Chotos {
    public Chotos corent(Chotos ong);
}

public class Fellnor implements Chotos {
    public Chotos corent(Chotos ong) {
        return new Fellnor();
    }
}

public class Wersan implements Chotos {
    public Chotos corent(Chotos ong) {
        return this;
    }
}

...and given the following setup code:

Chotos foo = new Fellnor();
Chotos bar = new Wersan();

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.corent(foo).corent(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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