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 Board 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 Board, and based on these observations, apply Extract Interface, too.
1 | <?php |
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5 | final class Board |
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6 | { |
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7 | private $width; |
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8 | private $height; |
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9 | private $fieldTypes = []; |
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10 | private $fields = []; |
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11 | private $actors = []; |
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12 | private $exits = []; |
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13 | private $functions = []; |
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14 | private $variables = []; |
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15 | private $actions = []; |
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16 | |||
17 | private static $moveMap = [ |
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18 | 'left' => [0, -1], |
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19 | 'right' => [0, 1], |
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20 | 'up' => [-1, 0], |
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21 | 'down' => [1, 0], |
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22 | ]; |
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23 | |||
24 | public function __construct(int $width, int $height) |
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29 | |||
30 | /* --- METHODS --- */ |
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31 | |||
32 | /** |
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33 | * @param ActionInterface[] $actions |
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34 | */ |
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35 | public function addActions(array $actions) |
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41 | |||
42 | public function addAction(ActionInterface $action) |
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46 | |||
47 | public function getAction(string $alias): ActionInterface |
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55 | |||
56 | public function addFieldTypes(array $types) |
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62 | |||
63 | public function hasAction($alias): bool |
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67 | |||
68 | public function addFieldType($alias, $symbol) |
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72 | |||
73 | public function loadFromString($string) |
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86 | |||
87 | public function addActor($alias, $x, $y, $direction) |
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97 | |||
98 | public function addExit($alias, $x, $y) |
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105 | |||
106 | public function addFunctions(array $functions) |
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112 | |||
113 | public function addFunction($name, array $program) |
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117 | |||
118 | public function isActorAtExit($actor, $exit): bool |
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125 | |||
126 | public function runActor($alias) |
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130 | |||
131 | public function runActorProgram($alias, array $program) |
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137 | |||
138 | private function runActorOperation($alias, array $operation) |
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142 | |||
143 | public function getActorNextMove($alias): array |
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150 | |||
151 | public function setVariable($name, $value) |
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155 | |||
156 | public function getVariable($name) |
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160 | |||
161 | public function getFunction($name) |
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165 | |||
166 | public function moveActor($alias) |
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189 | |||
190 | public function debug(...$args) |
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193 | |||
194 | public function setField($x, $y, $field) |
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198 | |||
199 | public function getField($x, $y) |
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203 | |||
204 | public function getActorDirection($alias) |
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208 | |||
209 | public function setActorDirection($alias, $direction) |
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213 | |||
214 | public function getActorPick($alias) |
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218 | |||
219 | public function setActorPick($alias, $pick) |
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223 | |||
224 | public function getActorPosition($alias): array |
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228 | |||
229 | public function renderBoard(): string |
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257 | |||
258 | /* --- GETTERS --- */ |
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259 | |||
260 | public function getWidth(): int |
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264 | |||
265 | public function getHeight(): int |
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269 | } |
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270 |
Late static binding only has effect in subclasses. A
final
class cannot be extended anymore so late static binding cannot occurr. Consider replacingstatic::
withself::
.To learn more about late static binding, please refer to the PHP core documentation.