Complex classes like Requirements_Backend_For_Webpack 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 Requirements_Backend_For_Webpack, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 10 | class Requirements_Backend_For_Webpack extends Requirements_Backend implements flushable  | 
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| 11 | { | 
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| 12 | |||
| 13 | /**  | 
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| 14 | * @var string  | 
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| 15 | */  | 
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| 16 | private static $webpack_variables_file_location = 'themes/webpack-variables.js';  | 
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| 17 | |||
| 18 | /**  | 
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| 19 | * we need this method because Requirements_Backend does not extend Object!  | 
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| 20 | * @param string  | 
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| 21 | */  | 
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| 22 | public static function set_webpack_variables_file_location($str)  | 
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| 23 |     { | 
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| 24 | self::$webpack_variables_file_location = $tr;  | 
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| 25 | }  | 
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| 26 | |||
| 27 | /**  | 
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| 28 | * IMPORTANT ... you will use this one more than others ...  | 
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| 29 | * e.g. /mysite/javascript/test.js  | 
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| 30 | * @var array  | 
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| 31 | */  | 
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| 32 | private static $files_to_ignore = [];  | 
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| 33 | |||
| 34 | /**  | 
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| 35 | * we need this method because Requirements_Backend does not extend Object!  | 
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| 36 | * @var array $array  | 
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| 37 | */  | 
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| 38 | public static function set_files_to_ignore($array)  | 
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| 42 | |||
| 43 | /**  | 
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| 44 | * @return array  | 
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| 45 | */  | 
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| 46 | public static function get_files_to_ignore()  | 
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| 50 | |||
| 51 | /**  | 
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| 52 | * @var string  | 
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| 53 | */  | 
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| 54 | private static $working_theme_folder_extension = "mysite";  | 
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| 55 | |||
| 56 | /**  | 
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| 57 | * we need this method because Requirements_Backend does not extend Object!  | 
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| 58 | * @var string $string  | 
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| 59 | */  | 
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| 60 | public static function set_working_theme_folder_extension($string)  | 
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| 64 | |||
| 65 | |||
| 66 | /**  | 
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| 67 | * we need this method because Requirements_Backend does not extend Object!  | 
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| 68 | * @return string  | 
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| 69 | */  | 
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| 70 | public static function get_working_theme_folder_extension()  | 
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| 74 | |||
| 75 | /**  | 
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| 76 | * @var string  | 
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| 77 | */  | 
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| 78 | private static $copy_css_to_folder = "src/raw_requirements/css";  | 
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| 79 | |||
| 80 | /**  | 
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| 81 | * we need this method because Requirements_Backend does not extend Object!  | 
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| 82 | * @var string $string  | 
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| 83 | */  | 
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| 84 | public static function set_copy_css_to_folder($string)  | 
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| 88 | |||
| 89 | /**  | 
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| 90 | * @var string  | 
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| 91 | */  | 
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| 92 | private static $copy_js_to_folder = "src/raw_requirements/js";  | 
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| 93 | |||
| 94 | /**  | 
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| 95 | * we need this method because Requirements_Backend does not extend Object!  | 
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| 96 | * @param string $string  | 
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| 97 | */  | 
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| 98 | public static function set_copy_js_to_folder($string)  | 
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| 102 | |||
| 103 | /**  | 
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| 104 | * @var array  | 
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| 105 | */  | 
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| 106 | private static $urls_to_exclude = array();  | 
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| 107 | |||
| 108 | /**  | 
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| 109 | * we need this method because Requirements_Backend does not extend Object!  | 
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| 110 | * @param array $array  | 
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| 111 | */  | 
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| 112 | public static function set_urls_to_exclude($a)  | 
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| 116 | |||
| 117 | /**  | 
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| 118 | *  | 
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| 119 | * @return array  | 
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| 120 | */  | 
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| 121 | public static function get_urls_to_exclude()  | 
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| 125 | |||
| 126 | /**  | 
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| 127 | * @var bool  | 
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| 128 | */  | 
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| 129 | private static $force_update = true;  | 
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| 130 | |||
| 131 | /**  | 
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| 132 | *  | 
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| 133 | * @param bool  | 
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| 134 | */  | 
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| 135 | public static function set_force_update($bool)  | 
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| 139 | |||
| 140 | |||
| 141 | /**  | 
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| 142 | *  | 
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| 143 | * @return bool  | 
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| 144 | */  | 
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| 145 | public static function get_force_update($bool)  | 
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| 149 | |||
| 150 | /**  | 
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| 151 | * Whether to add caching query params to the requests for file-based requirements.  | 
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| 152 | * Eg: themes/myTheme/js/main.js?m=123456789. The parameter is a timestamp generated by  | 
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| 153 | * filemtime. This has the benefit of allowing the browser to cache the URL infinitely,  | 
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| 154 | * while automatically busting this cache every time the file is changed.  | 
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| 155 | *  | 
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| 156 | * @var bool  | 
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| 157 | */  | 
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| 158 | protected $suffix_requirements = false;  | 
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| 159 | |||
| 160 | /**  | 
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| 161 | * Whether to combine CSS and JavaScript files  | 
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| 162 | *  | 
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| 163 | * @var bool  | 
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| 164 | */  | 
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| 165 | protected $combined_files_enabled = false;  | 
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| 166 | |||
| 167 | |||
| 168 | /**  | 
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| 169 | * Force the JavaScript to the bottom of the page, even if there's a script tag in the body already  | 
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| 170 | *  | 
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| 171 | * @var boolean  | 
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| 172 | */  | 
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| 173 | protected $force_js_to_bottom = true;  | 
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| 174 | |||
| 175 | |||
| 176 | /**  | 
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| 177 | * @return string  | 
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| 178 | */  | 
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| 179 | protected static function webpack_current_theme_as_set_in_db()  | 
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| 199 | |||
| 200 | |||
| 201 | /**  | 
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| 202 | * @return string  | 
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| 203 | */  | 
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| 204 | protected static function webpack_theme_folder_for_customisation()  | 
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| 208 | |||
| 209 | |||
| 210 | /**  | 
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| 211 | * Update the given HTML content with the appropriate include tags for the registered  | 
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| 212 | * requirements. Needs to receive a valid HTML/XHTML template in the $content parameter,  | 
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| 213 | * including a head and body tag.  | 
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| 214 | *  | 
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| 215 | * @param string $templateFile No longer used, only retained for compatibility  | 
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| 216 | * @param string $content HTML content that has already been parsed from the $templateFile  | 
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| 217 |      *                             through {@link SSViewer} | 
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| 218 | * @return string HTML content augmented with the requirements tags  | 
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| 219 | */  | 
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| 220 | public function includeInHTML($templateFile, $content)  | 
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| 323 | |||
| 324 | /**  | 
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| 325 | * Attach requirements inclusion to X-Include-JS and X-Include-CSS headers on the given  | 
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| 326 | * HTTP Response  | 
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| 327 | *  | 
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| 328 | * @param SS_HTTPResponse $response  | 
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| 329 | */  | 
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| 330 | public function include_in_response(SS_HTTPResponse $response)  | 
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| 340 | |||
| 341 | /**  | 
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| 342 | *  | 
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| 343 | *  | 
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| 344 | *  | 
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| 345 | * @return bool  | 
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| 346 | */  | 
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| 347 | protected function canSaveRequirements()  | 
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| 360 | |||
| 361 | /**  | 
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| 362 | *  | 
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| 363 | *  | 
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| 364 | * @return bool  | 
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| 365 | */  | 
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| 366 | protected function themedRequest()  | 
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| 370 | |||
| 371 | /**  | 
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| 372 | *  | 
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| 373 | * @param string $fileLocation  | 
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| 374 | * @param string $folderLocation  | 
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| 375 | *  | 
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| 376 | */  | 
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| 377 | protected function moveFileToRequirementsFolder($fileLocation, $folderLocation)  | 
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| 404 | |||
| 405 | protected function copyIfYouCan($from, $to, $count = 0)  | 
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| 417 | |||
| 418 | protected function addLinesToFile($fileLocation, $line, $count = 0)  | 
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| 441 | |||
| 442 | protected function makeFolderWritable($fileLocation)  | 
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| 451 | |||
| 452 | |||
| 453 | public static function flush()  | 
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| 491 | }  | 
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| 492 | 
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.