Complex classes like VirtualPage 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 VirtualPage, and based on these observations, apply Extract Interface, too.
1 | <?php |
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26 | class VirtualPage extends Page |
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27 | { |
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28 | |||
29 | private static $description = 'Displays the content of another page'; |
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30 | |||
31 | public static $virtualFields; |
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32 | |||
33 | /** |
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34 | * @var array Define fields that are not virtual - the virtual page must define these fields themselves. |
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35 | * Note that anything in {@link self::config()->initially_copied_fields} is implicitly included in this list. |
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36 | */ |
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37 | private static $non_virtual_fields = array( |
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38 | "ID", |
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39 | "ClassName", |
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40 | "ObsoleteClassName", |
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41 | "SecurityTypeID", |
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42 | "OwnerID", |
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43 | "ParentID", |
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44 | "URLSegment", |
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45 | "Sort", |
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46 | "Status", |
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47 | 'ShowInMenus', |
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48 | // 'Locale' |
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49 | 'ShowInSearch', |
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50 | 'Version', |
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51 | "Embargo", |
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52 | "Expiry", |
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53 | "CanViewType", |
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54 | "CanEditType", |
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55 | "CopyContentFromID", |
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56 | "HasBrokenLink", |
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57 | ); |
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58 | |||
59 | /** |
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60 | * @var array Define fields that are initially copied to virtual pages but left modifiable after that. |
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61 | */ |
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62 | private static $initially_copied_fields = array( |
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63 | 'ShowInMenus', |
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64 | 'ShowInSearch', |
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65 | 'URLSegment', |
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66 | ); |
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67 | |||
68 | private static $has_one = array( |
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69 | "CopyContentFrom" => "SilverStripe\\CMS\\Model\\SiteTree", |
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70 | ); |
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71 | |||
72 | private static $owns = array( |
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73 | "CopyContentFrom", |
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74 | ); |
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75 | |||
76 | private static $db = array( |
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77 | "VersionID" => "Int", |
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78 | ); |
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79 | |||
80 | private static $table_name = 'VirtualPage'; |
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81 | |||
82 | /** |
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83 | * Generates the array of fields required for the page type. |
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84 | * |
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85 | * @return array |
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86 | */ |
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87 | public function getVirtualFields() |
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100 | |||
101 | /** |
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102 | * List of fields or properties to never virtualise |
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103 | * |
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104 | * @return array |
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105 | */ |
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106 | public function getNonVirtualisedFields() |
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113 | |||
114 | public function setCopyContentFromID($val) |
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122 | |||
123 | public function ContentSource() |
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131 | |||
132 | /** |
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133 | * For VirtualPage, add a canonical link tag linking to the original page |
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134 | * See TRAC #6828 & http://support.google.com/webmasters/bin/answer.py?hl=en&answer=139394 |
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135 | * |
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136 | * @param boolean $includeTitle Show default <title>-tag, set to false for custom templating |
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137 | * @return string The XHTML metatags |
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138 | */ |
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139 | public function MetaTags($includeTitle = true) |
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149 | |||
150 | public function allowedChildren() |
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158 | |||
159 | public function syncLinkTracking() |
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168 | |||
169 | /** |
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170 | * We can only publish the page if there is a published source page |
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171 | * |
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172 | * @param Member $member Member to check |
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173 | * @return bool |
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174 | */ |
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175 | public function canPublish($member = null) |
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179 | |||
180 | /** |
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181 | * Returns true if is page is publishable by anyone at all |
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182 | * Return false if the source page isn't published yet. |
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183 | * |
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184 | * Note that isPublishable doesn't affect ete from live, only publish. |
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185 | */ |
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186 | public function isPublishable() |
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205 | |||
206 | /** |
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207 | * Generate the CMS fields from the fields from the original page. |
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208 | */ |
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209 | public function getCMSFields() |
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277 | |||
278 | public function onBeforeWrite() |
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283 | |||
284 | /** |
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285 | * Copy any fields from the copied record to bootstrap /backup |
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286 | */ |
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287 | protected function refreshFromCopied() |
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308 | |||
309 | public function getSettingsFields() |
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330 | |||
331 | public function validate() |
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351 | |||
352 | public function updateImageTracking() |
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365 | |||
366 | public function CMSTreeClasses() |
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370 | |||
371 | /** |
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372 | * Allow attributes on the master page to pass |
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373 | * through to the virtual page |
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374 | * |
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375 | * @param string $field |
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376 | * @return mixed |
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377 | */ |
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378 | public function __get($field) |
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391 | |||
392 | public function getField($field) |
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399 | |||
400 | /** |
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401 | * Check if given field is virtualised |
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402 | * |
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403 | * @param string $field |
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404 | * @return bool |
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405 | */ |
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406 | public function isFieldVirtualised($field) |
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423 | |||
424 | /** |
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425 | * Pass unrecognized method calls on to the original data object |
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426 | * |
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427 | * @param string $method |
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428 | * @param array $args |
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429 | * @return mixed |
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430 | */ |
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431 | public function __call($method, $args) |
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439 | |||
440 | /** |
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441 | * @param string $field |
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442 | * @return bool |
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443 | */ |
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444 | public function hasField($field) |
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452 | |||
453 | /** |
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454 | * Return the "casting helper" (a piece of PHP code that when evaluated creates a casted value object) for a field |
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455 | * on this object. |
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456 | * |
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457 | * @param string $field |
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458 | * @return string |
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459 | */ |
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460 | public function castingHelper($field) |
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468 | |||
469 | /** |
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470 | * {@inheritdoc} |
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471 | */ |
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472 | public function allMethodNames($custom = false) |
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482 | |||
483 | /** |
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484 | * {@inheritdoc} |
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485 | */ |
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486 | public function getControllerName() |
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494 | } |
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495 |
If you implement
__call
and you know which methods are available, you can improve IDE auto-completion and static analysis by adding a @method annotation to the class.This is often the case, when
__call
is implemented by a parent class and only the child class knows which methods exist: