Static and runtime types: Correct Solution

Given the following type declarations:

public class Sihack {
    public Sihack earher(Sihack vio) {
        return this;
    }
}

public class Etce extends Sihack {
    public Sihack earher(Sihack vio) {
        return vio;
    }
}

public class CinShrar extends Sihack {
    public Sihack earher(Sihack vio) {
        return new Etce();
    }
}

...and given the following setup code:

CinShrar foo = new CinShrar();
Sihack bar = new Etce();

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.earher(foo).earher(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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