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 Enum 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 Enum, and based on these observations, apply Extract Interface, too.
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16 | abstract class Enum |
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17 | { |
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18 | /** |
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19 | * The selected enumerator value |
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20 | * |
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21 | * @var null|bool|int|float|string |
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22 | */ |
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23 | private $value; |
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24 | |||
25 | /** |
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26 | * The ordinal number of the enumerator |
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27 | * |
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28 | * @var null|int |
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29 | */ |
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30 | private $ordinal; |
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31 | |||
32 | /** |
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33 | * A map of enumerator names and values by enumeration class |
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34 | * |
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35 | * @var array ["$class" => ["$name" => $value, ...], ...] |
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36 | */ |
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37 | private static $constants = array(); |
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38 | |||
39 | /** |
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40 | * A List of of available enumerator names by enumeration class |
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41 | * |
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42 | * @var array ["$class" => ["$name0", ...], ...] |
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43 | */ |
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44 | private static $names = array(); |
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45 | |||
46 | /** |
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47 | * Already instantiated enumerators |
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48 | * |
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49 | * @var array ["$class" => ["$name" => $instance, ...], ...] |
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50 | */ |
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51 | private static $instances = array(); |
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52 | |||
53 | /** |
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54 | * Constructor |
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55 | * |
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56 | * @param null|bool|int|float|string $value The value of the enumerator |
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57 | * @param int|null $ordinal The ordinal number of the enumerator |
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58 | */ |
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59 | 14 | final private function __construct($value, $ordinal = null) |
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64 | |||
65 | /** |
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66 | * Get the name of the enumerator |
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67 | * |
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68 | * @return string |
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69 | * @see getName() |
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70 | */ |
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71 | 1 | public function __toString() |
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75 | |||
76 | /** |
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77 | * @throws LogicException Enums are not cloneable |
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78 | * because instances are implemented as singletons |
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79 | */ |
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80 | 1 | final private function __clone() |
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84 | |||
85 | /** |
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86 | * @throws LogicException Enums are not serializable |
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87 | * because instances are implemented as singletons |
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88 | */ |
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89 | 1 | final public function __sleep() |
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93 | |||
94 | /** |
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95 | * @throws LogicException Enums are not serializable |
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96 | * because instances are implemented as singletons |
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97 | */ |
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98 | 1 | final public function __wakeup() |
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102 | |||
103 | /** |
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104 | * Get the value of the enumerator |
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105 | * |
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106 | * @return null|bool|int|float|string |
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107 | */ |
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108 | 21 | final public function getValue() |
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112 | |||
113 | /** |
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114 | * Get the name of the enumerator |
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115 | * |
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116 | * @return string |
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117 | */ |
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118 | 7 | final public function getName() |
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126 | |||
127 | /** |
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128 | * Get the ordinal number of the enumerator |
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129 | * |
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130 | * @return int |
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131 | */ |
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132 | 40 | final public function getOrdinal() |
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151 | |||
152 | /** |
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153 | * Compare this enumerator against another and check if it's the same. |
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154 | * |
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155 | * @param mixed $enumerator |
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156 | * @return bool |
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157 | */ |
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158 | 2 | final public function is($enumerator) |
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168 | |||
169 | /** |
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170 | * Get an enumerator instance of the given value or instance |
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171 | * |
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172 | * @param static|null|bool|int|float|string $value |
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173 | * @return static |
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174 | * @throws InvalidArgumentException On an unknwon or invalid value |
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175 | * @throws LogicException On ambiguous constant values |
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176 | */ |
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177 | 61 | final public static function get($value) |
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185 | |||
186 | /** |
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187 | * Get an enumerator instance by the given value |
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188 | * |
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189 | * @param mixed $value |
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190 | * @return static |
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191 | * @throws InvalidArgumentException On an unknwon or invalid value |
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192 | * @throws LogicException On ambiguous constant values |
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193 | */ |
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194 | 46 | final public static function byValue($value) |
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212 | |||
213 | /** |
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214 | * Get an enumerator instance by the given name |
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215 | * |
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216 | * @param string $name The name of the enumerator |
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217 | * @return static |
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218 | * @throws InvalidArgumentException On an invalid or unknown name |
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219 | * @throws LogicException On ambiguous values |
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220 | */ |
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221 | 32 | final public static function byName($name) |
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236 | |||
237 | /** |
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238 | * Get an enumeration instance by the given ordinal number |
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239 | * |
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240 | * @param int $ordinal The ordinal number or the enumerator |
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241 | * @return static |
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242 | * @throws InvalidArgumentException On an invalid ordinal number |
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243 | * @throws LogicException On ambiguous values |
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244 | */ |
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245 | 19 | final public static function byOrdinal($ordinal) |
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269 | |||
270 | /** |
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271 | * Get a list of enumerator instances ordered by ordinal number |
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272 | * |
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273 | * @return static[] |
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274 | */ |
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275 | 12 | final public static function getEnumerators() |
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282 | |||
283 | /** |
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284 | * Get a list of enumerator values ordered by ordinal number |
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285 | * |
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286 | * @return mixed[] |
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287 | */ |
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288 | 1 | final public static function getValues() |
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292 | |||
293 | /** |
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294 | * Get a list of enumerator names ordered by ordinal number |
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295 | * |
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296 | * @return string[] |
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297 | */ |
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298 | 1 | final public static function getNames() |
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305 | /* |
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306 | * Get a list of enumerator ordinal numbers |
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307 | * |
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308 | * @return int[] |
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309 | */ |
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310 | 1 | final public static function getOrdinals() |
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315 | |||
316 | /** |
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317 | * Get all available constants of the called class |
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318 | * |
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319 | * @return array |
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320 | * @throws LogicException On ambiguous constant values |
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321 | */ |
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322 | 63 | final public static function getConstants() |
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326 | |||
327 | /** |
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328 | * Is the given enumerator part of this enumeration |
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329 | * |
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330 | * @param static|null|bool|int|float|string $value |
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331 | * @return bool |
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332 | */ |
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333 | 1 | final public static function has($value) |
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342 | |||
343 | /** |
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344 | * Detect all public available constants of given enumeration class |
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345 | * |
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346 | * @param string $class |
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347 | * @return array |
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348 | * @throws LogicException On ambiguous constant values |
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349 | */ |
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350 | 80 | private static function detectConstants($class) |
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397 | |||
398 | /** |
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399 | * Get an enumerator instance by the given name. |
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400 | * |
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401 | * This will be called automatically on calling a method |
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402 | * with the same name of a defined enumerator. |
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403 | * |
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404 | * @param string $method The name of the enumeraotr (called as method) |
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405 | * @param array $args There should be no arguments |
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406 | * @return static |
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407 | * @throws InvalidArgumentException On an invalid or unknown name |
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408 | * @throws LogicException On ambiguous constant values |
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409 | */ |
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410 | 18 | final public static function __callStatic($method, array $args) |
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414 | } |
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415 |