Code Smell 55 - Object Orgy

Code Smell 55 - Object Orgy

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If you see your objects as data holders you will violate their encapsulation, but you shouldn't, as in real life, you should always ask for consent.

TL;DR: Don't mess with other object's data.

Problems

  • Information Hiding Violation

  • Encapsulation Violation

  • Coupling

Solutions

  1. Couple to interfaces and behavior, never data.

Sample Code

Wrong

<?

final class Point {
    public $x;
    public $y;
}

final class DistanceCalculator {
    function distanceBetween(Point $origin, Point $destination) {
        return sqrt((($destination->x - $origin->x) ^ 2) + (($destination->y - $origin->y) ^ 2));
    }
}
<?

final class Point {
    private $rho;
    private $theta;

    public function x() {
        return $this->rho * cos($this->theta);
    }

    public function y() {
        return $this->rho * sin($this->theta);
    }
}

final class DistanceCalculator {
    function distanceBetween(Point $origin, Point $destination) {

        return sqrt((($destination->x() - $origin->x() ^ 2) + (($destination->y() - $origin->y()) ^ 2)));
    }

}

Detection

You can set your linters to warn you for public attributes, setters and getters usage and discourage them.

Tags

  • Coupling

Conclusion

If your classes are polluted with setters, getters and public methods you will certainly have ways to couple to their accidental implementation.

Also Known as

  • Inappropriate intimacy

Relations

More info

Credits

Picture by Nicolas Poussin


A data structure is just a stupid programming language.

Bill Gosper



This article is part of the CodeSmell Series.

Last update: 2021/06/14

 
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