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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| 10 | class JukeboxService |
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| 11 | { |
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| 12 | /** @var JukeboxMap[] */ |
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| 13 | protected $mapQueue = []; |
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| 14 | |||
| 15 | /** |
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| 16 | * @var PlayerStorage |
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| 17 | */ |
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| 18 | private $playerStorage; |
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| 19 | /** |
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| 20 | * @var AdminGroups |
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| 21 | */ |
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| 22 | private $adminGroups; |
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| 23 | |||
| 24 | /** |
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| 25 | * JukeboxService constructor. |
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| 26 | * @param PlayerStorage $playerStorage |
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| 27 | * @param AdminGroups $adminGroups |
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| 28 | */ |
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| 29 | public function __construct(PlayerStorage $playerStorage, AdminGroups $adminGroups) |
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| 34 | |||
| 35 | /** |
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| 36 | * @return JukeboxMap[] |
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| 37 | */ |
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| 38 | public function getMapQueue() |
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| 42 | |||
| 43 | /** |
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| 44 | * @return JukeboxMap|null |
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| 45 | */ |
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| 46 | public function getFirst() |
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| 52 | |||
| 53 | /** |
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| 54 | * @param Map $map |
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| 55 | * @param null $login |
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| 56 | * @param bool $force |
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| 57 | * @return bool |
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| 58 | * @throws \Exception |
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| 59 | */ |
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| 60 | public function addMap(Map $map, $login = null, $force = false) |
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| 93 | |||
| 94 | /** |
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| 95 | * @param Map $map |
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| 96 | * @param $login |
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| 97 | * @param bool $force |
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| 98 | * @return bool |
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| 99 | * @throws \Exception |
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| 100 | */ |
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| 101 | public function removeMap(Map $map, $login = null, $force = false) |
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| 125 | |||
| 126 | /** |
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| 127 | * @param JukeboxMap $map |
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| 128 | */ |
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| 129 | private function add(JukeboxMap $map) |
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| 133 | |||
| 134 | /** |
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| 135 | * @param $login |
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| 136 | * @return bool|JukeboxMap |
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| 137 | */ |
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| 138 | public function getMap($login) |
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| 148 | |||
| 149 | /** |
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| 150 | * @param Map $map |
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| 151 | * |
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| 152 | * @return bool |
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| 153 | */ |
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| 154 | View Code Duplication | private function remove(Map $map) |
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| 166 | |||
| 167 | |||
| 168 | /** |
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| 169 | * checks if login exists on queue |
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| 170 | * @param string $login |
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| 171 | * @return bool |
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| 172 | */ |
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| 173 | private function checkLogin($login) |
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| 183 | |||
| 184 | /** |
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| 185 | * checks if map exists on queue |
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| 186 | * @param Map $map |
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| 187 | * @return bool |
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| 188 | */ |
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| 189 | View Code Duplication | private function checkMap(Map $map) |
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| 199 | |||
| 200 | /** |
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| 201 | * |
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| 202 | */ |
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| 203 | public function clearMapQueue() |
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| 207 | |||
| 208 | } |
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| 209 |
This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently.
Both the
$myVarassignment in line 1 and the$higherassignment in line 2 are dead. The first because$myVaris never used and the second because$higheris always overwritten for every possible time line.