Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like Provider often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Provider, and based on these observations, apply Extract Interface, too.
1 | <?php |
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21 | class Provider implements IProvider { |
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22 | |||
23 | /** @var MiscService */ |
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24 | protected $miscService; |
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25 | |||
26 | /** @var IL10N */ |
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27 | protected $l10n; |
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28 | |||
29 | /** @var IURLGenerator */ |
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30 | protected $url; |
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31 | |||
32 | /** @var IManager */ |
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33 | protected $activityManager; |
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34 | |||
35 | public function __construct( |
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43 | |||
44 | |||
45 | /** |
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46 | * @param string $lang |
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47 | * @param IEvent $event |
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48 | * @param IEvent|null $previousEvent |
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49 | * |
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50 | * @return IEvent |
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51 | */ |
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52 | public function parse($lang, IEvent $event, IEvent $previousEvent = null) { |
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63 | |||
64 | |||
65 | /** |
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66 | * @param string $lang |
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67 | * @param IEvent $event |
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68 | * |
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69 | * @return IEvent |
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70 | * @throws Exception |
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71 | */ |
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72 | private function parseAsMember($lang, IEvent $event) { |
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96 | |||
97 | |||
98 | /** |
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99 | * @param $lang |
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100 | * @param Circle $circle |
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101 | * @param IEvent $event |
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102 | * |
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103 | * @return IEvent |
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104 | */ |
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105 | private function parseMembersAsMember($lang, Circle $circle, IEvent $event) { |
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131 | |||
132 | |||
133 | /** |
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134 | * @param string $lang |
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135 | * @param IEvent $event |
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136 | * |
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137 | * @return IEvent |
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138 | */ |
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139 | private function parseAsModerator($lang, IEvent $event) { |
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164 | |||
165 | /** |
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166 | * @param string $lang |
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167 | * @param Circle $circle |
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168 | * @param IEvent $event |
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169 | * |
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170 | * @return IEvent |
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171 | */ |
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172 | View Code Duplication | private function parseCircleCreate($lang, Circle $circle, IEvent $event) { |
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196 | |||
197 | |||
198 | /** |
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199 | * @param string $lang |
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200 | * @param Circle $circle |
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201 | * @param IEvent $event |
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202 | * |
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203 | * @return IEvent |
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204 | */ |
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205 | View Code Duplication | private function parseCircleDelete($lang, Circle $circle, IEvent $event) { |
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228 | |||
229 | |||
230 | /** |
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231 | * @param string $lang |
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232 | * @param Circle $circle |
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233 | * @param Member $member |
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234 | * @param IEvent $event |
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235 | * |
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236 | * @return IEvent |
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237 | */ |
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238 | View Code Duplication | private function parseMemberInvited($lang, Circle $circle, Member $member, IEvent $event) { |
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279 | |||
280 | |||
281 | /** |
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282 | * @param $lang |
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283 | * @param Circle $circle |
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284 | * @param Member $member |
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285 | * @param IEvent $event |
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286 | * |
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287 | * @return IEvent |
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288 | */ |
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289 | private function parseMemberRequestInvitation( |
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311 | |||
312 | |||
313 | /** |
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314 | * @param $lang |
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315 | * @param Circle $circle |
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316 | * @param Member $member |
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317 | * @param IEvent $event |
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318 | * |
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319 | * @return IEvent |
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320 | */ |
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321 | View Code Duplication | private function parseMemberJoin($lang, Circle $circle, Member $member, IEvent $event) { |
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343 | |||
344 | |||
345 | /** |
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346 | * @param $lang |
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347 | * @param Circle $circle |
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348 | * @param Member $member |
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349 | * @param IEvent $event |
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350 | * |
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351 | * @return IEvent |
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352 | */ |
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353 | View Code Duplication | private function parseMemberAdd($lang, Circle $circle, Member $member, IEvent $event) { |
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395 | |||
396 | |||
397 | /** |
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398 | * @param $lang |
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399 | * @param Circle $circle |
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400 | * @param Member $member |
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401 | * @param IEvent $event |
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402 | * |
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403 | * @return IEvent |
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404 | */ |
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405 | View Code Duplication | private function parseMemberLeft($lang, Circle $circle, Member $member, IEvent $event) { |
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427 | |||
428 | |||
429 | /** |
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430 | * @param $lang |
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431 | * @param Circle $circle |
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432 | * @param Member $member |
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433 | * @param IEvent $event |
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434 | * |
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435 | * @return IEvent |
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436 | */ |
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437 | View Code Duplication | private function parseMemberRemove($lang, Circle $circle, Member $member, IEvent $event) { |
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479 | |||
480 | |||
481 | |||
482 | // |
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483 | // |
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484 | // /** |
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485 | // * @param string $lang |
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486 | // * @param IEvent $event |
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487 | // * |
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488 | // * @return IEvent |
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489 | // */ |
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490 | // private function parsePopulation($lang, IEvent $event) { |
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491 | // if ($event->getType() !== 'circles_population') { |
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492 | // return $event; |
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493 | // } |
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494 | // |
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495 | // return $event; |
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496 | // } |
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497 | // |
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498 | // |
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499 | // /** |
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500 | // * @param string $lang |
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501 | // * @param IEvent $event |
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502 | // * |
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503 | // * @return IEvent |
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504 | // */ |
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505 | // private function parseRights($lang, IEvent $event) { |
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506 | // if ($event->getType() !== 'circles_rights') { |
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507 | // return $event; |
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508 | // } |
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509 | // |
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510 | // return $event; |
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511 | // } |
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512 | // |
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513 | // |
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514 | // /** |
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515 | // * @param string $lang |
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516 | // * @param IEvent $event |
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517 | // * |
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518 | // * @return IEvent |
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519 | // */ |
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520 | // private function parseShares($lang, IEvent $event) { |
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521 | // if ($event->getType() !== 'circles_shares') { |
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522 | // return $event; |
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523 | // } |
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524 | // |
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525 | // return $event; |
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526 | // } |
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527 | // |
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528 | // private function parseMood(IEvent &$event, $mood) { |
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529 | // |
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530 | // if (key_exists('website', $mood)) { |
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531 | // $event->setRichMessage( |
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532 | // $mood['text'] . '{opengraph}', |
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533 | // ['opengraph' => $this->generateOpenGraphParameter('_id_', $mood['website'])] |
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534 | // ); |
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535 | // } else { |
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536 | // $event->setParsedMessage($mood['text']); |
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537 | // } |
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538 | // |
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539 | // } |
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540 | |||
541 | |||
542 | private function parseActivityHeader(IEvent &$event, SharingFrame $frame) { |
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584 | |||
585 | |||
586 | private function generateCircleParameter(Circle $circle) { |
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596 | |||
597 | |||
598 | private function generateMemberParameter(Member $member) { |
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601 | |||
602 | /** |
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603 | * @param $userId |
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604 | * |
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605 | * @return array |
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606 | */ |
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607 | private function generateUserParameter($userId) { |
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614 | } |
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615 |
Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.
You can also find more detailed suggestions in the “Code” section of your repository.