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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| 17 | class RandomOrgAPI implements RandomOrgAPIInterface  | 
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| 18 | { | 
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| 19 | /**  | 
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| 20 | * The default Random.org endpoint.  | 
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| 21 | *  | 
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| 22 | * @var string;  | 
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| 23 | */  | 
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| 24 | private $endpoint = 'https://api.random.org/json-rpc/1/invoke';  | 
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| 25 | |||
| 26 | /**  | 
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| 27 | * The configuration.  | 
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| 28 | *  | 
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| 29 | * @var array  | 
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| 30 | */  | 
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| 31 | private $configuration;  | 
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| 32 | |||
| 33 | /**  | 
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| 34 | * The HTTP client.  | 
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| 35 | *  | 
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| 36 | * @var \Http\Client\HttpClient  | 
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| 37 | */  | 
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| 38 | private $httpClient;  | 
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| 39 | |||
| 40 | /**  | 
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| 41 | * RandomOrgAPI constructor.  | 
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| 42 | *  | 
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| 43 | * @param \Http\Client\HttpClient $httpClient  | 
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| 44 | * The HTTP client.  | 
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| 45 | * @param array $configuration  | 
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| 46 | * The configuration array.  | 
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| 47 | *  | 
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| 48 | * @SuppressWarnings(PHPMD.StaticAccess)  | 
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| 49 | */  | 
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| 50 | 10 | public function __construct(HttpClient $httpClient = null, array $configuration = [])  | 
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| 85 | |||
| 86 | /**  | 
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| 87 |      * {@inheritdoc} | 
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| 88 | */  | 
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| 89 | 3 | public function withApiKey(string $apikey) :RandomOrgAPIInterface  | 
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| 99 | |||
| 100 | /**  | 
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| 101 |      * {@inheritdoc} | 
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| 102 | */  | 
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| 103 | 2 | public function withEndPoint(string $endpoint) :RandomOrgAPIInterface  | 
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| 110 | |||
| 111 | /**  | 
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| 112 |      * {@inheritdoc} | 
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| 113 | */  | 
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| 114 | 1 | public function withHttpClient(HttpClient $client) :RandomOrgAPIInterface  | 
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| 121 | |||
| 122 | /**  | 
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| 123 |      * {@inheritdoc} | 
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| 124 | */  | 
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| 125 | 6 | public function getEndPoint() :string  | 
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| 129 | |||
| 130 | /**  | 
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| 131 |      * {@inheritdoc} | 
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| 132 | */  | 
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| 133 | 6 | public function getApiKey() :string  | 
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| 139 | |||
| 140 | /**  | 
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| 141 |      * {@inheritdoc} | 
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| 142 | */  | 
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| 143 | 5 | public function call(ProviderInterface $methodPlugin) :ResponseInterface  | 
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| 156 | |||
| 157 | /**  | 
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| 158 |      * {@inheritdoc} | 
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| 159 | */  | 
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| 160 | 3 | public function get(ProviderInterface $methodPlugin) :array  | 
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| 170 | |||
| 171 | /**  | 
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| 172 |      * {@inheritdoc} | 
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| 173 | */  | 
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| 174 | 2 | public function getData(ProviderInterface $methodPlugin)  | 
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| 188 | |||
| 189 | /**  | 
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| 190 |      * {@inheritdoc} | 
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| 191 | */  | 
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| 192 | 7 | public function getConfiguration() :array  | 
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| 196 | |||
| 197 | /**  | 
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| 198 |      * {@inheritdoc} | 
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| 199 | */  | 
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| 200 | 6 | public function getHttpClient() :HttpClient  | 
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| 204 | |||
| 205 | /**  | 
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| 206 | * Validate the response.  | 
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| 207 | *  | 
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| 208 | * @param \Psr\Http\Message\ResponseInterface $response  | 
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| 209 | *  | 
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| 210 | * @return \Exception|ResponseInterface  | 
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| 211 | */  | 
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| 212 | 5 | private function validateResponse(ResponseInterface $response) :ResponseInterface  | 
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| 252 | }  | 
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| 253 | 
This check looks for
@paramannotations where the type inferred by our type inference engine differs from the declared type.It makes a suggestion as to what type it considers more descriptive.
Most often this is a case of a parameter that can be null in addition to its declared types.