Complex classes like ApiClient 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 ApiClient, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 17 | class ApiClient  | 
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| 18 | { | 
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| 19 | const BASE_URL = 'https://slack.com/api/';  | 
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| 20 | const CONTENT_TYPE = 'application/x-www-form-urlencoded';  | 
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| 21 | |||
| 22 | private $arguments = [  | 
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| 23 | 'rtm.start' => [  | 
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| 24 | 'required' => [  | 
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| 25 | 'token',  | 
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| 26 | ],  | 
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| 27 | 'optional' => [  | 
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| 28 | 'simple_latest',  | 
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| 29 | 'no_unreads',  | 
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| 30 | 'mpim_aware',  | 
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| 31 | ],  | 
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| 32 | ],  | 
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| 33 | 'chat.postMessage' => [  | 
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| 34 | 'required' => [  | 
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| 35 | 'token',  | 
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| 36 | 'channel',  | 
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| 37 | 'text',  | 
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| 38 | ],  | 
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| 39 | 'optional' => [  | 
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| 40 | 'parse',  | 
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| 41 | 'link_names',  | 
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| 42 | 'attachments',  | 
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| 43 | 'unfurl_links',  | 
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| 44 | 'unfurl_media',  | 
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| 45 | 'username',  | 
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| 46 | 'as_user',  | 
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| 47 | 'icon_url',  | 
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| 48 | 'icon_emoji',  | 
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| 49 | ],  | 
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| 50 | ],  | 
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| 51 | 'oauth.access' => [  | 
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| 52 | 'required' => [  | 
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| 53 | 'client_id',  | 
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| 54 | 'client_secret',  | 
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| 55 | 'code',  | 
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| 56 | ],  | 
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| 57 | 'optional' => [  | 
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| 58 | 'redirect_uri',  | 
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| 59 | ],  | 
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| 60 | ],  | 
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| 61 | 'team.info' => [  | 
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| 62 | 'required' => [  | 
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| 63 | 'token',  | 
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| 64 | ],  | 
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| 65 | ],  | 
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| 66 | 'im.list' => [  | 
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| 67 | 'required' => [  | 
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| 68 | 'token',  | 
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| 69 | ],  | 
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| 70 | ],  | 
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| 71 | 'users.list' => [  | 
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| 72 | 'required' => [  | 
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| 73 | 'token',  | 
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| 74 | ],  | 
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| 75 | 'optional' => [  | 
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| 76 | 'presence',  | 
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| 77 | ],  | 
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| 78 | ],  | 
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| 79 | 'users.info' => [  | 
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| 80 | 'required' => [  | 
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| 81 | 'token',  | 
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| 82 | 'user',  | 
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| 83 | ],  | 
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| 84 | ],  | 
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| 85 | ];  | 
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| 86 | |||
| 87 | private $client;  | 
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| 88 | private $token;  | 
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| 89 | private $arrayUtility;  | 
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| 90 | |||
| 91 | /**  | 
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| 92 | * ApiClient constructor.  | 
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| 93 | *  | 
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| 94 | * @param null $token  | 
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| 95 | */  | 
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| 96 | 43 | public function __construct($token = null)  | 
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| 100 | |||
| 101 | /**  | 
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| 102 | * API CURL Call with post method.  | 
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| 103 | *  | 
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| 104 | * @param string $method  | 
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| 105 | * @param array $arguments  | 
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| 106 | *  | 
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| 107 | * @throws \Exception  | 
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| 108 | *  | 
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| 109 | * @return mixed  | 
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| 110 | */  | 
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| 111 | 33 | public function apiCall($method, array $arguments = [])  | 
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| 121 | |||
| 122 | 30 | private function sendRequest($method, $requestBody)  | 
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| 132 | |||
| 133 | /**  | 
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| 134 | * @param $method  | 
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| 135 | * @param array $arguments  | 
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| 136 | *  | 
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| 137 | * @throws \Exception  | 
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| 138 | *  | 
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| 139 | * @return string  | 
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| 140 | */  | 
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| 141 | 33 | private function prepareRequestBody($method, array $arguments = [])  | 
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| 155 | |||
| 156 | /**  | 
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| 157 | * @param $response  | 
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| 158 | *  | 
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| 159 | * @throws \Exception  | 
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| 160 | *  | 
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| 161 | * @return mixed  | 
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| 162 | */  | 
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| 163 | 28 | private function processResponse($response)  | 
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| 173 | |||
| 174 | /**  | 
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| 175 | * @throws \Exception  | 
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| 176 | *  | 
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| 177 | * @return array  | 
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| 178 | */  | 
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| 179 | 34 | public function getArgs()  | 
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| 190 | |||
| 191 | /**  | 
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| 192 | * @param $arguments  | 
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| 193 | *  | 
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| 194 | * @return mixed  | 
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| 195 | */  | 
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| 196 | 2 | public function chatPostMessage($arguments)  | 
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| 200 | |||
| 201 | /**  | 
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| 202 | * @param $arguments  | 
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| 203 | *  | 
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| 204 | * @throws \Exception  | 
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| 205 | *  | 
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| 206 | * @return mixed  | 
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| 207 | */  | 
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| 208 | 1 | public function rtmStart($arguments)  | 
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| 212 | |||
| 213 | /**  | 
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| 214 | * @throws \Exception  | 
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| 215 | *  | 
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| 216 | * @return array  | 
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| 217 | * @return Team  | 
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| 218 | */  | 
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| 219 | 4 | public function teamInfo()  | 
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| 229 | |||
| 230 | /**  | 
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| 231 | * @return null|\Botonomous\AbstractBaseSlack  | 
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| 232 | */  | 
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| 233 | 2 | public function teamInfoAsObject()  | 
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| 245 | |||
| 246 | /**  | 
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| 247 | * List all the Slack users in the team.  | 
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| 248 | *  | 
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| 249 | * @return array  | 
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| 250 | */  | 
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| 251 | 2 | public function usersList()  | 
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| 261 | |||
| 262 | /**  | 
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| 263 | * Return a user by Slack user id.  | 
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| 264 | *  | 
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| 265 | * @param $arguments  | 
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| 266 | *  | 
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| 267 | * @throws \Exception  | 
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| 268 | *  | 
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| 269 | * @return mixed  | 
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| 270 | */  | 
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| 271 | 10 | public function userInfo($arguments)  | 
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| 282 | |||
| 283 | /**  | 
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| 284 | * @throws \Exception  | 
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| 285 | *  | 
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| 286 | * @return mixed  | 
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| 287 | */  | 
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| 288 | 1 | public function test()  | 
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| 292 | |||
| 293 | /**  | 
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| 294 | * @throws \Exception  | 
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| 295 | *  | 
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| 296 | * @return array  | 
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| 297 | */  | 
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| 298 | 5 | public function imList()  | 
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| 308 | |||
| 309 | /**  | 
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| 310 | * @return array  | 
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| 311 | */  | 
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| 312 | 4 | public function imListAsObject()  | 
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| 327 | |||
| 328 | /**  | 
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| 329 | * @param $arguments  | 
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| 330 | *  | 
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| 331 | * @throws \Exception  | 
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| 332 | *  | 
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| 333 | * @return mixed  | 
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| 334 | */  | 
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| 335 | 5 | public function oauthAccess($arguments)  | 
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| 339 | |||
| 340 | /** @noinspection PhpUndefinedClassInspection  | 
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| 341 | * @param Client $client  | 
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| 342 | */  | 
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| 343 | 33 | public function setClient(Client $client)  | 
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| 347 | |||
| 348 | /** @noinspection PhpUndefinedClassInspection  | 
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| 349 | * @return Client|null  | 
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| 350 | */  | 
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| 351 | 30 | public function getClient()  | 
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| 360 | |||
| 361 | /**  | 
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| 362 | * @param $method  | 
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| 363 | * @param $arguments  | 
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| 364 | *  | 
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| 365 | * @throws \Exception  | 
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| 366 | *  | 
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| 367 | * @return bool  | 
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| 368 | */  | 
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| 369 | 33 | private function validateRequiredArguments($method, $arguments)  | 
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| 385 | |||
| 386 | /**  | 
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| 387 | * @param null $method  | 
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| 388 | *  | 
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| 389 | * @throws \Exception  | 
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| 390 | *  | 
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| 391 | * @return mixed  | 
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| 392 | */  | 
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| 393 | 35 | public function getArguments($method = null)  | 
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| 406 | |||
| 407 | /**  | 
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| 408 | * @param array $arguments  | 
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| 409 | */  | 
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| 410 | 1 | public function setArguments(array $arguments)  | 
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| 414 | |||
| 415 | /**  | 
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| 416 | * @param $method  | 
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| 417 | * @param array $arguments  | 
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| 418 | *  | 
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| 419 | * @return array  | 
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| 420 | */  | 
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| 421 | 31 | public function filterArguments($method, array $arguments)  | 
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| 437 | |||
| 438 | /**  | 
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| 439 | * @return string  | 
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| 440 | */  | 
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| 441 | 34 | public function getToken()  | 
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| 450 | |||
| 451 | /**  | 
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| 452 | * @param string $token  | 
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| 453 | */  | 
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| 454 | 43 | public function setToken($token)  | 
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| 458 | |||
| 459 | /**  | 
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| 460 | * @return ArrayUtility  | 
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| 461 | */  | 
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| 462 | 30 | public function getArrayUtility()  | 
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| 470 | |||
| 471 | /**  | 
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| 472 | * @param ArrayUtility $arrayUtility  | 
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| 473 | */  | 
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| 474 | 30 | public function setArrayUtility(ArrayUtility $arrayUtility)  | 
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| 478 | }  | 
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| 479 | 
Overly long lines are hard to read on any screen. Most code styles therefor impose a maximum limit on the number of characters in a line.