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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| 15 | final class Validator  | 
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| 16 | { | 
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| 17 | /**  | 
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| 18 | * @var ObjectFacade  | 
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| 19 | */  | 
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| 20 | private $facade;  | 
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| 21 | |||
| 22 | /**  | 
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| 23 | * Validator constructor.  | 
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| 24 | *  | 
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| 25 | * @param ObjectFacade $facade  | 
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| 26 | */  | 
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| 27 | public function __construct(ObjectFacade $facade)  | 
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| 31 | |||
| 32 | /**  | 
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| 33 | * @param ObjectFacade $facade  | 
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| 34 | *  | 
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| 35 | * @return Validator  | 
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| 36 | */  | 
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| 37 | public static function new(ObjectFacade $facade): self  | 
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| 41 | |||
| 42 | /**  | 
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| 43 | * @param ReflectionProperty $property  | 
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| 44 | *  | 
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| 45 | * @return bool  | 
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| 46 | */  | 
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| 47 | public function isValidProperty(ReflectionProperty $property): bool  | 
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| 63 | |||
| 64 | /**  | 
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| 65 | * @param ReflectionMethod $method  | 
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| 66 | *  | 
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| 67 | * @return bool  | 
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| 68 | */  | 
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| 69 | public function isValidMethod(ReflectionMethod $method): bool  | 
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| 85 | |||
| 86 | /**  | 
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| 87 | * @param ReflectionMethod $method  | 
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| 88 | * @param $value  | 
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| 89 | *  | 
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| 90 | * @return bool  | 
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| 91 | */  | 
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| 92 | public function isValidSetterMethod(ReflectionMethod $method, $value): bool  | 
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| 130 | |||
| 131 | /**  | 
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| 132 | * @param ReflectionParameter $parameter  | 
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| 133 | * @param $value  | 
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| 134 | *  | 
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| 135 | * @return bool  | 
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| 136 | */  | 
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| 137 | public function isValidValue(ReflectionParameter $parameter, $value): bool  | 
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| 141 | |||
| 142 | /**  | 
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| 143 | * @param ReflectionMethod $method  | 
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| 144 | *  | 
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| 145 | * @return bool  | 
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| 146 | */  | 
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| 147 | public function validateGetterMethod(ReflectionMethod $method): bool  | 
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| 162 | }  |