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 User 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 User, and based on these observations, apply Extract Interface, too.
1 | <?php |
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49 | class User implements IUser { |
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50 | use EventEmitterTrait; |
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51 | /** @var Account */ |
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52 | private $account; |
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53 | |||
54 | /** @var Emitter|Manager $emitter */ |
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55 | private $emitter; |
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56 | |||
57 | /** @var \OCP\IConfig $config */ |
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58 | private $config; |
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59 | |||
60 | /** @var IAvatarManager */ |
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61 | private $avatarManager; |
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62 | |||
63 | /** @var IURLGenerator */ |
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64 | private $urlGenerator; |
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65 | |||
66 | /** @var EventDispatcher */ |
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67 | private $eventDispatcher; |
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68 | |||
69 | /** @var AccountMapper */ |
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70 | private $mapper; |
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71 | |||
72 | /** @var \OC\Group\Manager */ |
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73 | private $groupManager; |
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74 | |||
75 | /** @var Session */ |
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76 | private $userSession; |
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77 | |||
78 | /** |
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79 | * User constructor. |
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80 | * |
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81 | * @param Account $account |
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82 | * @param AccountMapper $mapper |
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83 | * @param null $emitter |
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84 | * @param IConfig|null $config |
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85 | * @param null $urlGenerator |
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86 | * @param EventDispatcher|null $eventDispatcher |
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87 | * @param \OC\Group\Manager|null $groupManager |
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88 | * @param Session|null $userSession |
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89 | */ |
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90 | public function __construct(Account $account, AccountMapper $mapper, $emitter = null, IConfig $config = null, |
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115 | |||
116 | /** |
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117 | * get the user id |
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118 | * |
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119 | * @return string |
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120 | */ |
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121 | public function getUID() { |
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124 | |||
125 | /** |
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126 | * get the display name for the user, if no specific display name is set it will fallback to the user id |
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127 | * |
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128 | * @return string |
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129 | */ |
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130 | public function getDisplayName() { |
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137 | |||
138 | /** |
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139 | * set the displayname for the user |
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140 | * |
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141 | * @param string $displayName |
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142 | * @return bool |
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143 | */ |
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144 | public function setDisplayName($displayName) { |
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164 | |||
165 | /** |
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166 | * set the email address of the user |
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167 | * |
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168 | * @param string|null $mailAddress |
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169 | * @return void |
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170 | * @since 9.0.0 |
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171 | */ |
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172 | public function setEMailAddress($mailAddress) { |
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181 | |||
182 | /** |
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183 | * returns the timestamp of the user's last login or 0 if the user did never |
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184 | * login |
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185 | * |
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186 | * @return int |
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187 | */ |
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188 | public function getLastLogin() { |
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191 | |||
192 | /** |
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193 | * updates the timestamp of the most recent login of this user |
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194 | */ |
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195 | public function updateLastLoginTimestamp() { |
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201 | |||
202 | /** |
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203 | * Delete the user |
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204 | * |
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205 | * @return bool |
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206 | */ |
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207 | public function delete() { |
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252 | |||
253 | /** |
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254 | * Set the user's password |
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255 | * |
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256 | * @param string $password |
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257 | * @param string $recoveryPassword for the encryption app to reset encryption keys |
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258 | * @return bool |
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259 | * @throws ArgumentNotSetException |
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260 | */ |
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261 | public function setPassword($password, $recoveryPassword = null) { |
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293 | |||
294 | /** |
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295 | * get the users home folder to mount |
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296 | * |
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297 | * @return string |
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298 | */ |
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299 | public function getHome() { |
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302 | |||
303 | /** |
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304 | * Get the name of the backend class the user is connected with |
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305 | * |
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306 | * @return string |
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307 | */ |
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308 | public function getBackendClassName() { |
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315 | |||
316 | /** |
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317 | * check if the backend allows the user to change his avatar on Personal page |
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318 | * |
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319 | * @return bool |
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320 | */ |
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321 | public function canChangeAvatar() { |
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331 | |||
332 | /** |
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333 | * check if the backend supports changing passwords |
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334 | * |
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335 | * @return bool |
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336 | */ |
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337 | public function canChangePassword() { |
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344 | |||
345 | /** |
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346 | * check if the backend supports changing display names |
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347 | * |
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348 | * @return bool |
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349 | */ |
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350 | public function canChangeDisplayName() { |
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368 | |||
369 | /** |
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370 | * check if the user is enabled |
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371 | * |
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372 | * @return bool |
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373 | */ |
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374 | public function isEnabled() { |
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377 | |||
378 | /** |
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379 | * set the enabled status for the user |
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380 | * |
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381 | * @param bool $enabled |
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382 | */ |
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383 | public function setEnabled($enabled) { |
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395 | |||
396 | /** |
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397 | * get the users email address |
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398 | * |
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399 | * @return string|null |
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400 | * @since 9.0.0 |
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401 | */ |
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402 | public function getEMailAddress() { |
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405 | |||
406 | /** |
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407 | * get the users' quota |
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408 | * |
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409 | * @return string |
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410 | * @since 9.0.0 |
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411 | */ |
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412 | public function getQuota() { |
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419 | |||
420 | /** |
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421 | * set the users' quota |
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422 | * |
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423 | * @param string $quota |
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424 | * @return void |
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425 | * @since 9.0.0 |
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426 | */ |
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427 | public function setQuota($quota) { |
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436 | |||
437 | /** |
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438 | * get the avatar image if it exists |
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439 | * |
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440 | * @param int $size |
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441 | * @return IImage|null |
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442 | * @since 9.0.0 |
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443 | */ |
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444 | public function getAvatarImage($size) { |
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458 | |||
459 | /** |
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460 | * get the federation cloud id |
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461 | * |
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462 | * @return string |
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463 | * @since 9.0.0 |
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464 | */ |
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465 | public function getCloudId() { |
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470 | |||
471 | /** |
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472 | * @param string $url |
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473 | * @return string |
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474 | */ |
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475 | View Code Duplication | private function removeProtocolFromUrl($url) { |
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484 | |||
485 | public function triggerChange($feature, $value = null) { |
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490 | |||
491 | /** |
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492 | * @return string[] |
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493 | * @since 10.0.1 |
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494 | */ |
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495 | public function getSearchTerms() { |
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502 | |||
503 | /** |
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504 | * @param string[] $terms |
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505 | * @since 10.0.1 |
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506 | */ |
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507 | public function setSearchTerms(array $terms) { |
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514 | } |
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515 |
Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different implementation of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the interface: