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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| 4 | class BannerPageTypesManager  | 
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| 5 | { | 
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| 6 | |||
| 7 | const PAGE_TYPE_MAIN = 'main';  | 
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| 8 | const PAGE_TYPE_SHOP_CATEGORY = 'shop_category';  | 
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| 9 | const PAGE_TYPE_PRODUCT = 'product';  | 
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| 10 | const PAGE_TYPE_CATEGORY = 'category';  | 
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| 11 | const PAGE_TYPE_PAGE = 'page';  | 
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| 12 | const PAGE_TYPE_BRAND = 'brand';  | 
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| 13 | const PAGE_TYPE_SEARCH = 'search';  | 
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| 14 | |||
| 15 | /**  | 
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| 16 | * @var BannerPageTypesManager instance  | 
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| 17 | */  | 
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| 18 | private static $instance = NULL;  | 
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| 19 | |||
| 20 |     private function __construct() { | 
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| 23 | |||
| 24 | /**  | 
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| 25 | * Get BannerPageTypesManager instance  | 
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| 26 | * @return BannerPageTypesManager instance  | 
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| 27 | */  | 
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| 28 |     public static function getInstance() { | 
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| 34 | |||
| 35 | /**  | 
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| 36 | * Get banner pages type|types: ['main', 'shop_category', 'product',...] on nothing to get all types array  | 
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| 37 | * @param string $type - banner type  | 
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| 38 | * @return array  | 
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| 39 | */  | 
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| 40 |     public function getPagesTypes($type = NULL) { | 
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| 74 | |||
| 75 | /**  | 
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| 76 | * Get banner type view  | 
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| 77 | * @param string $type - banner page type name type: ['main', 'shop_category', 'product',...]  | 
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| 78 | * @param string $locale - locale name  | 
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| 79 | * @return array  | 
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| 80 | */  | 
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| 81 | View Code Duplication |     public function getView($type, $locale = NULL) { | 
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| 93 | |||
| 94 | /**  | 
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| 95 | * Get banner page type allowed pages list  | 
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| 96 | * @param string $type - banner page type name type: ['main', 'shop_category', 'product',...]  | 
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| 97 | * @param string $locale - locale name  | 
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| 98 | * @return array  | 
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| 99 | */  | 
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| 100 | View Code Duplication |     public function getPages($type, $locale = NULL) { | 
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| 112 | }  |