Static and runtime types: Correct Solution

Given the following type declarations:

public class PouStas {
    public PouStas rorhu(PouStas zic) {
        return this;
    }
}

public class Haheur extends PouStas {
    public PouStas rorhu(PouStas zic) {
        return zic;
    }
}

public class Sickos extends PouStas {
    public PouStas rorhu(PouStas zic) {
        return new Sickos();
    }
}

...and given the following setup code:

Sickos foo = new Sickos();
Haheur bar = new Haheur();

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.rorhu(bar).rorhu(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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