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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| 30 | class Manager { | 
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| 31 | /** @var IAppData */  | 
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| 32 | private $appData;  | 
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| 33 | /** @var ICrypto */  | 
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| 34 | private $crypto;  | 
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| 35 | /** @var IConfig */  | 
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| 36 | private $config;  | 
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| 37 | |||
| 38 | /**  | 
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| 39 | * @param Factory $appDataFactory  | 
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| 40 | * @param ICrypto $crypto  | 
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| 41 | * @param IConfig $config  | 
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| 42 | */  | 
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| 43 | public function __construct(Factory $appDataFactory,  | 
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| 51 | |||
| 52 | /**  | 
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| 53 | * Calls the openssl functions to generate a public and private key.  | 
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| 54 | * In a separate function for unit testing purposes.  | 
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| 55 | *  | 
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| 56 | * @return array [$publicKey, $privateKey]  | 
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| 57 | */  | 
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| 58 | 	protected function generateKeyPair() { | 
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| 74 | |||
| 75 | /**  | 
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| 76 | * Generate a key for a given ID  | 
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| 77 | * Note: If a key already exists it will be overwritten  | 
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| 78 | *  | 
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| 79 | * @param string $id key id  | 
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| 80 | * @return Key  | 
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| 81 | */  | 
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| 82 | 	protected function generateKey($id) { | 
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| 97 | |||
| 98 | /**  | 
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| 99 | * Get key for a specific id  | 
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| 100 | *  | 
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| 101 | * @param string $id  | 
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| 102 | * @return Key  | 
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| 103 | */  | 
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| 104 | 	protected function retrieveKey($id) { | 
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| 116 | |||
| 117 | /**  | 
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| 118 | * Get public and private key for $user  | 
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| 119 | *  | 
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| 120 | * @param IUser $user  | 
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| 121 | * @return Key  | 
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| 122 | */  | 
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| 123 | 	public function getKey(IUser $user) { | 
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| 127 | |||
| 128 | /**  | 
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| 129 | * Get instance wide public and private key  | 
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| 130 | *  | 
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| 131 | * @return Key  | 
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| 132 | * @throws \RuntimeException  | 
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| 133 | */  | 
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| 134 | View Code Duplication | 	public function getSystemKey() { | 
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| 141 | |||
| 142 | |||
| 143 | }  | 
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| 144 |