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 Router 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 Router, and based on these observations, apply Extract Interface, too.
1 | <?php |
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11 | class Router |
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12 | { |
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13 | /** |
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14 | * Reference to instantiated controller object. |
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15 | * |
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16 | * @var object |
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17 | */ |
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18 | protected static $instance = false; |
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19 | |||
20 | /** |
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21 | * System configuration |
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22 | * |
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23 | * @var object |
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24 | */ |
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25 | private $configuration; |
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26 | |||
27 | /** |
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28 | * The active module |
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29 | * |
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30 | * @var string |
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31 | * @access public |
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32 | */ |
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33 | public $module; |
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34 | |||
35 | /** |
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36 | * The active controller |
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37 | * |
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38 | * @var string |
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39 | * @access public |
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40 | */ |
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41 | public $controller; |
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42 | |||
43 | /** |
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44 | * The active method |
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45 | * |
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46 | * @var string |
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47 | * @access public |
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48 | */ |
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49 | public $method; |
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50 | |||
51 | /** |
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52 | * The base URL |
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53 | * |
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54 | * @var string |
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55 | * @access public |
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56 | */ |
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57 | public $baseURL; |
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58 | |||
59 | /** |
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60 | * Default module |
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61 | * |
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62 | * @var string |
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63 | * @access public |
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64 | */ |
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65 | public $defaultModule; |
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66 | |||
67 | /** |
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68 | * Default controller |
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69 | * |
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70 | * @var string |
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71 | * @access public |
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72 | */ |
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73 | public $defaultController; |
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74 | |||
75 | /** |
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76 | * Default method |
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77 | * |
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78 | * @var string |
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79 | * @access public |
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80 | */ |
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81 | public $defaultMethod; |
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82 | |||
83 | /** |
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84 | * Default uri |
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85 | * |
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86 | * @var string |
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87 | * @access public |
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88 | */ |
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89 | public $uri; |
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90 | /** |
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91 | * Load up some basic configuration settings. |
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92 | */ |
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93 | 28 | public function __construct() |
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131 | |||
132 | |||
133 | 28 | private function isURIClean($uri, $uriChunks) |
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150 | |||
151 | //@TODO add Security class. |
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152 | 26 | private function normalize($data) |
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164 | |||
165 | /** |
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166 | * Parse and explode URI segments into chunks |
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167 | * |
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168 | * @access private |
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169 | * |
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170 | * @param string $uri |
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171 | * |
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172 | * @return array chunks of uri |
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173 | * @throws RouteException on disallowed characters |
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174 | */ |
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175 | 28 | private function parseURI($uri) |
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203 | |||
204 | /** |
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205 | * Normalize the $_SERVER vars for formatting the URI. |
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206 | * |
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207 | * @access private |
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208 | * @return string formatted/u/r/l |
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209 | */ |
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210 | 28 | private function normalizeURI() |
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232 | |||
233 | private function discoverRoute($uri) |
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262 | |||
263 | /** |
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264 | * Normalize the $_SERVER vars for formatting the URI. |
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265 | * |
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266 | * @access public |
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267 | * @return string formatted/u/r/l |
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268 | */ |
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269 | 28 | private function uri($uri) |
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282 | |||
283 | 28 | private function sortURISegments($uriChunks = []) |
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319 | |||
320 | 2 | private function addQueryString($url, $key, $value) |
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330 | |||
331 | 2 | private function removeQueryString($url, $key) |
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337 | |||
338 | /** |
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339 | * Return the currentURL w/ query strings |
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340 | * |
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341 | * @access public |
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342 | * @return string http://tld.com/formatted/u/r/l?q=bingo |
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343 | */ |
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344 | 28 | public function currentURL($params = false) |
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363 | |||
364 | /** |
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365 | * Return the baseURL |
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366 | * |
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367 | * @access public |
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368 | * @return string http://tld.com |
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369 | */ |
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370 | 28 | public function baseURL($path = '') |
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397 | |||
398 | /** |
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399 | * Set optional status header, and redirect to provided URL |
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400 | * |
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401 | * @access public |
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402 | * @return bool |
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403 | */ |
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404 | public function redirect($url = '/', $status = null) |
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455 | } |
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456 |
In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code:
Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: