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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14 | class Column |
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15 | { |
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16 | /** |
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17 | * @var Grid |
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18 | */ |
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19 | protected $grid; |
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20 | |||
21 | /** |
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22 | * Name of column. |
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23 | * |
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24 | * @var string |
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25 | */ |
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26 | protected $name; |
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27 | |||
28 | /** |
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29 | * Label of column. |
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30 | * |
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31 | * @var string |
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32 | */ |
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33 | protected $label; |
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34 | |||
35 | /** |
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36 | * Original value of column. |
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37 | * |
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38 | * @var mixed |
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39 | */ |
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40 | protected $original; |
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41 | |||
42 | /** |
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43 | * Is column sortable. |
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44 | * |
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45 | * @var bool |
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46 | */ |
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47 | protected $sortable = false; |
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48 | |||
49 | /** |
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50 | * Sort arguments. |
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51 | * |
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52 | * @var array |
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53 | */ |
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54 | protected $sort; |
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55 | |||
56 | /** |
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57 | * Attributes of column. |
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58 | * |
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59 | * @var array |
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60 | */ |
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61 | protected $attributes = []; |
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62 | |||
63 | /** |
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64 | * Relation name. |
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65 | * |
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66 | * @var bool |
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67 | */ |
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68 | protected $relation = false; |
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69 | |||
70 | /** |
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71 | * Relation column. |
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72 | * |
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73 | * @var string |
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74 | */ |
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75 | protected $relationColumn; |
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76 | |||
77 | /** |
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78 | * Original grid data. |
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79 | * |
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80 | * @var array |
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81 | */ |
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82 | protected static $originalGridData = []; |
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83 | |||
84 | /** |
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85 | * @var []Closure |
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86 | */ |
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87 | protected $displayCallbacks = []; |
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88 | |||
89 | /** |
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90 | * Displayers for grid column. |
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91 | * |
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92 | * @var array |
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93 | */ |
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94 | public static $displayers = []; |
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95 | |||
96 | /** |
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97 | * Defined columns. |
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98 | * |
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99 | * @var array |
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100 | */ |
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101 | public static $defined = []; |
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102 | |||
103 | /** |
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104 | * @var array |
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105 | */ |
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106 | protected static $htmlAttributes = []; |
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107 | |||
108 | /** |
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109 | * @var |
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110 | */ |
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111 | protected static $model; |
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112 | |||
113 | const SELECT_COLUMN_NAME = '__row_selector__'; |
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114 | |||
115 | /** |
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116 | * @param string $name |
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117 | * @param string $label |
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118 | */ |
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119 | public function __construct($name, $label) |
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125 | |||
126 | /** |
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127 | * Extend column displayer. |
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128 | * |
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129 | * @param $name |
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130 | * @param $displayer |
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131 | */ |
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132 | public static function extend($name, $displayer) |
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136 | |||
137 | /** |
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138 | * Define a column globally. |
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139 | * |
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140 | * @param string $name |
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141 | * @param mixed $definition |
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142 | */ |
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143 | public static function define($name, $definition) |
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147 | |||
148 | /** |
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149 | * Set grid instance for column. |
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150 | * |
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151 | * @param Grid $grid |
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152 | */ |
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153 | public function setGrid(Grid $grid) |
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159 | |||
160 | /** |
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161 | * Set model for column. |
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162 | * |
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163 | * @param $model |
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164 | */ |
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165 | public function setModel($model) |
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171 | |||
172 | /** |
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173 | * Set original data for column. |
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174 | * |
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175 | * @param array $input |
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176 | */ |
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177 | public static function setOriginalGridData(array $input) |
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181 | |||
182 | /** |
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183 | * Set column attributes. |
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184 | * |
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185 | * @param array $attributes |
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186 | * |
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187 | * @return $this |
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188 | */ |
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189 | public function setAttributes($attributes = []) |
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195 | |||
196 | /** |
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197 | * Get column attributes. |
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198 | * |
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199 | * @param string $name |
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200 | * |
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201 | * @return mixed |
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202 | */ |
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203 | public static function getAttributes($name) |
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207 | |||
208 | /** |
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209 | * Set style of this column. |
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210 | * |
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211 | * @param string $style |
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212 | * |
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213 | * @return Column |
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214 | */ |
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215 | public function style($style) |
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219 | |||
220 | /** |
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221 | * Get name of this column. |
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222 | * |
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223 | * @return mixed |
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224 | */ |
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225 | public function getName() |
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229 | |||
230 | /** |
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231 | * Format label. |
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232 | * |
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233 | * @param $label |
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234 | * |
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235 | * @return mixed |
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236 | */ |
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237 | protected function formatLabel($label) |
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243 | |||
244 | /** |
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245 | * Get label of the column. |
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246 | * |
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247 | * @return mixed |
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248 | */ |
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249 | public function getLabel() |
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253 | |||
254 | /** |
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255 | * Set relation. |
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256 | * |
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257 | * @param string $relation |
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258 | * @param string $relationColumn |
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259 | * |
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260 | * @return $this |
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261 | */ |
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262 | public function setRelation($relation, $relationColumn = null) |
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269 | |||
270 | /** |
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271 | * If this column is relation column. |
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272 | * |
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273 | * @return bool |
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274 | */ |
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275 | protected function isRelation() |
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279 | |||
280 | /** |
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281 | * Mark this column as sortable. |
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282 | * |
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283 | * @return Column |
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284 | */ |
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285 | public function sortable() |
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291 | |||
292 | /** |
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293 | * Add a display callback. |
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294 | * |
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295 | * @param Closure $callback |
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296 | * |
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297 | * @return $this |
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298 | */ |
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299 | public function display(Closure $callback) |
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305 | |||
306 | /** |
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307 | * If has display callbacks. |
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308 | * |
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309 | * @return bool |
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310 | */ |
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311 | protected function hasDisplayCallbacks() |
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315 | |||
316 | /** |
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317 | * Call all of the "display" callbacks column. |
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318 | * |
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319 | * @param mixed $value |
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320 | * @param int $key |
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321 | * |
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322 | * @return mixed |
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323 | */ |
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324 | protected function callDisplayCallbacks($value, $key) |
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333 | |||
334 | /** |
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335 | * Set original grid data to column. |
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336 | * |
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337 | * @param Closure $callback |
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338 | * @param int $key |
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339 | * |
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340 | * @return Closure |
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341 | */ |
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342 | protected function bindOriginalRow(Closure $callback, $key) |
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348 | |||
349 | /** |
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350 | * Fill all data to every column. |
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351 | * |
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352 | * @param array $data |
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353 | * |
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354 | * @return mixed |
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355 | */ |
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356 | public function fill(array $data) |
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377 | |||
378 | /** |
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379 | * If current column is a defined column. |
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380 | * |
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381 | * @return bool |
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382 | */ |
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383 | protected function isDefinedColumn() |
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387 | |||
388 | /** |
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389 | * Use a defined column. |
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390 | * |
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391 | * @throws \Exception |
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392 | */ |
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393 | protected function useDefinedColumn() |
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419 | |||
420 | /** |
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421 | * Convert characters to HTML entities recursively. |
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422 | * |
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423 | * @param array|string $item |
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424 | * |
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425 | * @return mixed |
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426 | */ |
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427 | protected function htmlEntityEncode($item) |
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439 | |||
440 | /** |
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441 | * Create the column sorter. |
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442 | * |
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443 | * @return string|void |
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444 | */ |
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445 | public function sorter() |
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466 | |||
467 | /** |
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468 | * Determine if this column is currently sorted. |
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469 | * |
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470 | * @return bool |
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471 | */ |
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472 | protected function isSorted() |
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482 | |||
483 | /** |
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484 | * Find a displayer to display column. |
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485 | * |
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486 | * @param string $abstract |
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487 | * @param array $arguments |
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488 | * |
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489 | * @return Column |
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490 | */ |
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491 | protected function resolveDisplayer($abstract, $arguments) |
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499 | |||
500 | /** |
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501 | * Call Illuminate/Support displayer. |
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502 | * |
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503 | * @param string $abstract |
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504 | * @param array $arguments |
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505 | * |
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506 | * @return Column |
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507 | */ |
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508 | protected function callSupportDisplayer($abstract, $arguments) |
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522 | |||
523 | /** |
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524 | * Call Builtin displayer. |
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525 | * |
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526 | * @param string $abstract |
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527 | * @param array $arguments |
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528 | * |
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529 | * @return Column |
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530 | */ |
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531 | protected function callBuiltinDisplayer($abstract, $arguments) |
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566 | |||
567 | /** |
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568 | * Passes through all unknown calls to builtin displayer or supported displayer. |
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569 | * |
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570 | * Allow fluent calls on the Column object. |
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571 | * |
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572 | * @param string $method |
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573 | * @param array $arguments |
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574 | * |
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575 | * @return $this |
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576 | */ |
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577 | public function __call($method, $arguments) |
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591 | } |
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592 |
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: