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 BaseElement 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 BaseElement, and based on these observations, apply Extract Interface, too.
1 | <?php |
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6 | class BaseElement extends Widget |
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7 | { |
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8 | /** |
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9 | * @var array $db |
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10 | */ |
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11 | private static $db = array( |
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12 | 'ExtraClass' => 'Varchar(255)', |
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13 | 'HideTitle' => 'Boolean' |
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14 | ); |
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15 | |||
16 | /** |
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17 | * @var array $has_one |
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18 | */ |
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19 | private static $has_one = array( |
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20 | 'List' => 'ElementList' // optional. |
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21 | ); |
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22 | |||
23 | /** |
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24 | * @var array $has_many |
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25 | */ |
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26 | private static $has_many = array( |
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27 | 'VirtualClones' => 'ElementVirtualLinked' |
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28 | ); |
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29 | |||
30 | /** |
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31 | * @var string |
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32 | */ |
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33 | private static $title = "Content Block"; |
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34 | |||
35 | /** |
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36 | * @var string |
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37 | */ |
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38 | private static $singular_name = 'Content Block'; |
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39 | |||
40 | /** |
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41 | * @var array |
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42 | */ |
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43 | private static $summary_fields = array( |
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44 | 'ID' => 'ID', |
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45 | 'Title' => 'Title', |
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46 | 'ElementType' => 'Type' |
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47 | ); |
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48 | |||
49 | /** |
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50 | * @var array |
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51 | */ |
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52 | private static $searchable_fields = array( |
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53 | 'ID' => array( |
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54 | 'field' => 'NumericField' |
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55 | ), |
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56 | 'Title', |
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57 | 'LastEdited', |
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58 | 'ClassName' |
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59 | ); |
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60 | |||
61 | /** |
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62 | * @var boolean |
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63 | */ |
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64 | private static $enable_title_in_template = false; |
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65 | |||
66 | /** |
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67 | * @var Object |
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68 | * The virtual owner VirtualLinkedElement |
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69 | */ |
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70 | public $virtualOwner; |
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71 | |||
72 | |||
73 | public function getCMSFields() |
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153 | |||
154 | /** |
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155 | * Version viewer must only be added at if this is the final getCMSFields for a class. |
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156 | * in order to avoid having to rename all fields from eg Root.Main to Root.Current.Main |
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157 | * To do this we test if getCMSFields is from the current class |
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158 | */ |
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159 | public function isEndofLine($className) |
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169 | |||
170 | |||
171 | public function onBeforeWrite() |
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185 | |||
186 | /** |
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187 | * Ensure that if there are elements that are virtualised from this element |
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188 | * that we move the original element to replace one of the virtual elements |
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189 | * But only if it's a delete not an unpublish |
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190 | */ |
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191 | public function onBeforeDelete() { |
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243 | |||
244 | /** |
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245 | * @return string |
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246 | */ |
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247 | public function i18n_singular_name() |
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251 | |||
252 | /** |
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253 | * @return string |
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254 | */ |
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255 | public function getElementType() |
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259 | |||
260 | /** |
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261 | * @return string |
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262 | */ |
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263 | View Code Duplication | public function getTitle() |
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275 | |||
276 | /** |
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277 | * @return string |
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278 | */ |
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279 | View Code Duplication | public function getCMSTitle() |
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290 | |||
291 | public function ControllerTop() |
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295 | |||
296 | public function getPage() |
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310 | |||
311 | /** |
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312 | * Override the {@link Widget::forTemplate()} method so that holders are not rendered twice. The controller should |
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313 | * render with widget inside the |
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314 | * |
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315 | * @return HTML |
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316 | */ |
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317 | public function forTemplate($holder = true) |
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321 | |||
322 | /** |
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323 | * @return string |
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324 | */ |
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325 | public function getEditLink() { |
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333 | |||
334 | public function onBeforeVersionedPublish() |
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338 | |||
339 | public static function all_allowed_elements() { |
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370 | |||
371 | public function getDefaultSearchContext() |
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387 | |||
388 | public function setVirtualOwner(ElementVirtualLinked $virtualOwner) { |
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391 | |||
392 | /** |
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393 | * Finds and returns elements |
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394 | * that are virtual elements which link to this element |
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395 | */ |
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396 | public function getVirtualLinkedElements() { |
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399 | |||
400 | /** |
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401 | * Finds and returns published elements |
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402 | * that are virtual elements which link to this element |
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403 | */ |
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404 | public function getPublishedVirtualLinkedElements() { |
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411 | } |
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412 | |||
414 |
You can fix this by adding a namespace to your class:
When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries.