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:
| 1 | <?php |
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| 8 | class DataProcessor |
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| 9 | { |
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| 10 | /** |
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| 11 | * @var int |
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| 12 | */ |
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| 13 | protected $start; |
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| 14 | |||
| 15 | /** |
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| 16 | * Columns to escape value. |
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| 17 | * |
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| 18 | * @var array |
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| 19 | */ |
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| 20 | protected $escapeColumns = []; |
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| 21 | |||
| 22 | /** |
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| 23 | * Processed data output. |
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| 24 | * |
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| 25 | * @var array |
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| 26 | */ |
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| 27 | protected $output = []; |
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| 28 | |||
| 29 | /** |
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| 30 | * @var array |
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| 31 | */ |
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| 32 | protected $appendColumns = []; |
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| 33 | |||
| 34 | /** |
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| 35 | * @var array |
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| 36 | */ |
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| 37 | protected $editColumns = []; |
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| 38 | |||
| 39 | /** |
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| 40 | * @var array |
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| 41 | */ |
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| 42 | protected $excessColumns = []; |
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| 43 | |||
| 44 | /** |
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| 45 | * @var mixed |
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| 46 | */ |
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| 47 | protected $results; |
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| 48 | |||
| 49 | /** |
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| 50 | * @var array |
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| 51 | */ |
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| 52 | protected $templates; |
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| 53 | |||
| 54 | /** |
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| 55 | * @var bool |
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| 56 | */ |
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| 57 | protected $includeIndex; |
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| 58 | |||
| 59 | /** |
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| 60 | * @var array |
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| 61 | */ |
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| 62 | protected $rawColumns; |
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| 63 | |||
| 64 | /** |
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| 65 | * @var array |
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| 66 | */ |
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| 67 | protected $exceptions = ['DT_RowId', 'DT_RowClass', 'DT_RowData', 'DT_RowAttr']; |
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| 68 | |||
| 69 | /** |
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| 70 | * @param mixed $results |
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| 71 | * @param array $columnDef |
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| 72 | * @param array $templates |
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| 73 | * @param int $start |
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| 74 | */ |
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| 75 | public function __construct($results, array $columnDef, array $templates, $start) |
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| 88 | |||
| 89 | /** |
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| 90 | * Process data to output on browser. |
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| 91 | * |
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| 92 | * @param bool $object |
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| 93 | * @return array |
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| 94 | */ |
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| 95 | public function process($object = false) |
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| 117 | |||
| 118 | /** |
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| 119 | * Process add columns. |
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| 120 | * |
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| 121 | * @param mixed $data |
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| 122 | * @param mixed $row |
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| 123 | * @return array |
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| 124 | */ |
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| 125 | View Code Duplication | protected function addColumns($data, $row) |
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| 134 | |||
| 135 | /** |
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| 136 | * Process edit columns. |
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| 137 | * |
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| 138 | * @param mixed $data |
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| 139 | * @param mixed $row |
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| 140 | * @return array |
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| 141 | */ |
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| 142 | View Code Duplication | protected function editColumns($data, $row) |
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| 151 | |||
| 152 | /** |
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| 153 | * Setup additional DT row variables. |
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| 154 | * |
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| 155 | * @param mixed $data |
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| 156 | * @param mixed $row |
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| 157 | * @return array |
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| 158 | */ |
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| 159 | protected function setupRowVariables($data, $row) |
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| 170 | |||
| 171 | /** |
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| 172 | * Get only needed columns. |
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| 173 | * |
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| 174 | * @param array $data |
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| 175 | * @return array |
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| 176 | */ |
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| 177 | protected function selectOnlyNeededColumns(array $data) |
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| 185 | |||
| 186 | /** |
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| 187 | * Remove declared hidden columns. |
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| 188 | * |
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| 189 | * @param array $data |
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| 190 | * @return array |
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| 191 | */ |
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| 192 | protected function removeExcessColumns(array $data) |
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| 200 | |||
| 201 | /** |
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| 202 | * Flatten array with exceptions. |
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| 203 | * |
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| 204 | * @param array $array |
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| 205 | * @return array |
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| 206 | */ |
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| 207 | public function flatten(array $array) |
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| 220 | |||
| 221 | /** |
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| 222 | * Escape column values as declared. |
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| 223 | * |
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| 224 | * @param array $output |
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| 225 | * @return array |
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| 226 | */ |
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| 227 | protected function escapeColumns(array $output) |
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| 242 | |||
| 243 | /** |
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| 244 | * Escape all values of row. |
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| 245 | * |
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| 246 | * @param array $row |
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| 247 | * @return array |
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| 248 | */ |
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| 249 | protected function escapeRow(array $row) |
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| 264 | } |
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| 265 |
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: