Static and runtime types: Correct Solution

Given the following type declarations:

public interface Asveic {
    public Asveic cirno(Asveic thra);
}

public class ErtOscra implements Asveic {
    public Asveic cirno(Asveic thra) {
        return this;
    }
}

public class Luss implements Asveic {
    public Asveic cirno(Asveic thra) {
        return thra;
    }
}

...and given the following setup code:

Luss foo = new Luss();
Asveic bar = new ErtOscra();

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.cirno(bar).cirno(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

Related puzzles: