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 Column 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 Column, and based on these observations, apply Extract Interface, too.
1 | <?php |
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13 | class Column |
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14 | { |
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15 | /** |
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16 | * @var Grid |
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17 | */ |
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18 | protected $grid; |
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19 | |||
20 | /** |
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21 | * Name of column. |
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22 | * |
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23 | * @var string |
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24 | */ |
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25 | protected $name; |
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26 | |||
27 | /** |
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28 | * Label of column. |
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29 | * |
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30 | * @var string |
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31 | */ |
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32 | protected $label; |
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33 | |||
34 | /** |
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35 | * Original value of column. |
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36 | * |
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37 | * @var mixed |
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38 | */ |
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39 | protected $original; |
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40 | |||
41 | /** |
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42 | * Is column sortable. |
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43 | * |
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44 | * @var bool |
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45 | */ |
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46 | protected $sortable = false; |
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47 | |||
48 | /** |
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49 | * Sort arguments. |
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50 | * |
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51 | * @var array |
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52 | */ |
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53 | protected $sort; |
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54 | |||
55 | /** |
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56 | * Attributes of column. |
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57 | * |
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58 | * @var array |
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59 | */ |
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60 | protected $attributes = []; |
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61 | |||
62 | /** |
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63 | * Relation name. |
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64 | * |
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65 | * @var bool |
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66 | */ |
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67 | protected $relation = false; |
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68 | |||
69 | /** |
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70 | * Relation column. |
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71 | * |
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72 | * @var string |
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73 | */ |
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74 | protected $relationColumn; |
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75 | |||
76 | /** |
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77 | * Original grid data. |
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78 | * |
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79 | * @var Collection |
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80 | */ |
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81 | protected static $originalGridModels; |
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82 | |||
83 | /** |
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84 | * @var []Closure |
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85 | */ |
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86 | protected $displayCallbacks = []; |
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87 | |||
88 | /** |
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89 | * Displayers for grid column. |
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90 | * |
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91 | * @var array |
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92 | */ |
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93 | public static $displayers = []; |
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94 | |||
95 | /** |
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96 | * Defined columns. |
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97 | * |
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98 | * @var array |
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99 | */ |
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100 | public static $defined = []; |
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101 | |||
102 | /** |
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103 | * @var array |
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104 | */ |
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105 | protected static $htmlAttributes = []; |
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106 | |||
107 | /** |
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108 | * @var Model |
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109 | */ |
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110 | protected static $model; |
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111 | |||
112 | const SELECT_COLUMN_NAME = '__row_selector__'; |
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113 | |||
114 | /** |
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115 | * @param string $name |
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116 | * @param string $label |
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117 | */ |
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118 | public function __construct($name, $label) |
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124 | |||
125 | /** |
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126 | * Extend column displayer. |
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127 | * |
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128 | * @param $name |
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129 | * @param $displayer |
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130 | */ |
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131 | public static function extend($name, $displayer) |
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135 | |||
136 | /** |
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137 | * Define a column globally. |
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138 | * |
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139 | * @param string $name |
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140 | * @param mixed $definition |
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141 | */ |
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142 | public static function define($name, $definition) |
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146 | |||
147 | /** |
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148 | * Set grid instance for column. |
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149 | * |
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150 | * @param Grid $grid |
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151 | */ |
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152 | public function setGrid(Grid $grid) |
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158 | |||
159 | /** |
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160 | * Set model for column. |
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161 | * |
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162 | * @param $model |
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163 | */ |
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164 | public function setModel($model) |
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170 | |||
171 | /** |
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172 | * Set original data for column. |
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173 | * |
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174 | * @param Collection $collection |
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175 | */ |
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176 | public static function setOriginalGridModels(Collection $collection) |
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177 | { |
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178 | static::$originalGridModels = $collection; |
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179 | } |
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180 | |||
181 | /** |
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182 | * Set column attributes. |
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183 | * |
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184 | * @param array $attributes |
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185 | * |
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186 | * @return $this |
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187 | */ |
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188 | public function setAttributes($attributes = []) |
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194 | |||
195 | /** |
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196 | * Get column attributes. |
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197 | * |
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198 | * @param string $name |
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199 | * |
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200 | * @return mixed |
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201 | */ |
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202 | public static function getAttributes($name) |
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206 | |||
207 | /** |
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208 | * Set style of this column. |
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209 | * |
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210 | * @param string $style |
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211 | * |
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212 | * @return Column |
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213 | */ |
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214 | public function style($style) |
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218 | |||
219 | /** |
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220 | * Get name of this column. |
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221 | * |
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222 | * @return mixed |
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223 | */ |
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224 | public function getName() |
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228 | |||
229 | /** |
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230 | * Format label. |
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231 | * |
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232 | * @param $label |
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233 | * |
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234 | * @return mixed |
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235 | */ |
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236 | protected function formatLabel($label) |
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242 | |||
243 | /** |
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244 | * Get label of the column. |
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245 | * |
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246 | * @return mixed |
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247 | */ |
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248 | public function getLabel() |
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252 | |||
253 | /** |
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254 | * Set relation. |
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255 | * |
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256 | * @param string $relation |
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257 | * @param string $relationColumn |
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258 | * |
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259 | * @return $this |
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260 | */ |
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261 | public function setRelation($relation, $relationColumn = null) |
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268 | |||
269 | /** |
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270 | * If this column is relation column. |
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271 | * |
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272 | * @return bool |
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273 | */ |
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274 | protected function isRelation() |
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278 | |||
279 | /** |
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280 | * Set sort value. |
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281 | * |
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282 | * @param bool $sort |
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283 | * |
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284 | * @return Column |
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285 | */ |
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286 | public function sort($sort) |
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292 | |||
293 | /** |
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294 | * Mark this column as sortable. |
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295 | * |
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296 | * @return Column |
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297 | */ |
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298 | public function sortable() |
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302 | |||
303 | /** |
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304 | * Add a display callback. |
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305 | * |
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306 | * @param Closure $callback |
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307 | * |
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308 | * @return $this |
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309 | */ |
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310 | public function display(Closure $callback) |
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316 | |||
317 | /** |
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318 | * Display using display abstract. |
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319 | * |
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320 | * @param string $abstract |
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321 | * @param array $arguments |
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322 | * |
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323 | * @return Column |
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324 | */ |
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325 | public function displayUsing($abstract, $arguments = []) |
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338 | |||
339 | /** |
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340 | * Display column using array value map. |
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341 | * |
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342 | * @param array $values |
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343 | * @param null $default |
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344 | * |
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345 | * @return $this |
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346 | */ |
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347 | View Code Duplication | public function using(array $values, $default = null) |
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357 | |||
358 | /** |
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359 | * Render this column with the given view. |
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360 | * |
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361 | * @param string $view |
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362 | * |
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363 | * @return $this |
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364 | */ |
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365 | public function view($view) |
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373 | |||
374 | /** |
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375 | * If has display callbacks. |
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376 | * |
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377 | * @return bool |
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378 | */ |
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379 | protected function hasDisplayCallbacks() |
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383 | |||
384 | /** |
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385 | * Call all of the "display" callbacks column. |
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386 | * |
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387 | * @param mixed $value |
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388 | * @param int $key |
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389 | * |
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390 | * @return mixed |
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391 | */ |
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392 | protected function callDisplayCallbacks($value, $key) |
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410 | |||
411 | /** |
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412 | * Set original grid data to column. |
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413 | * |
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414 | * @param Closure $callback |
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415 | * @param int $key |
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416 | * |
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417 | * @return Closure |
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418 | */ |
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419 | protected function bindOriginalRowModel(Closure $callback, $key) |
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425 | |||
426 | /** |
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427 | * Fill all data to every column. |
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428 | * |
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429 | * @param array $data |
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430 | * |
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431 | * @return mixed |
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432 | */ |
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433 | public function fill(array $data) |
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454 | |||
455 | /** |
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456 | * If current column is a defined column. |
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457 | * |
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458 | * @return bool |
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459 | */ |
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460 | protected function isDefinedColumn() |
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464 | |||
465 | /** |
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466 | * Use a defined column. |
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467 | * |
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468 | * @throws \Exception |
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469 | */ |
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470 | protected function useDefinedColumn() |
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497 | |||
498 | /** |
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499 | * Convert characters to HTML entities recursively. |
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500 | * |
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501 | * @param array|string $item |
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502 | * |
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503 | * @return mixed |
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504 | */ |
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505 | protected function htmlEntityEncode($item) |
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517 | |||
518 | /** |
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519 | * Create the column sorter. |
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520 | * |
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521 | * @return string |
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522 | */ |
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523 | public function sorter() |
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544 | |||
545 | /** |
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546 | * Determine if this column is currently sorted. |
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547 | * |
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548 | * @return bool |
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549 | */ |
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550 | protected function isSorted() |
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560 | |||
561 | /** |
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562 | * Find a displayer to display column. |
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563 | * |
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564 | * @param string $abstract |
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565 | * @param array $arguments |
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566 | * |
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567 | * @return Column |
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568 | */ |
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569 | protected function resolveDisplayer($abstract, $arguments) |
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577 | |||
578 | /** |
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579 | * Call Illuminate/Support displayer. |
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580 | * |
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581 | * @param string $abstract |
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582 | * @param array $arguments |
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583 | * |
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584 | * @return Column |
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585 | */ |
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586 | protected function callSupportDisplayer($abstract, $arguments) |
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600 | |||
601 | /** |
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602 | * Call Builtin displayer. |
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603 | * |
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604 | * @param string $abstract |
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605 | * @param array $arguments |
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606 | * |
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607 | * @return Column |
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608 | */ |
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609 | protected function callBuiltinDisplayer($abstract, $arguments) |
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631 | |||
632 | /** |
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633 | * Passes through all unknown calls to builtin displayer or supported displayer. |
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634 | * |
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635 | * Allow fluent calls on the Column object. |
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636 | * |
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637 | * @param string $method |
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638 | * @param array $arguments |
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639 | * |
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640 | * @return $this |
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641 | */ |
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642 | public function __call($method, $arguments) |
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655 | } |
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656 |
Let’s assume that you have a directory layout like this:
and let’s assume the following content of
Bar.php
:If both files
OtherDir/Foo.php
andSomeDir/Foo.php
are loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.php
However, as
OtherDir/Foo.php
does not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php
, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: