Complex classes like Response 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 Response, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 17 | class Response  | 
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| 18 | { | 
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| 19 | /**  | 
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| 20 | * Output format  | 
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| 21 | *  | 
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| 22 | * @var string  | 
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| 23 | */  | 
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| 24 | protected $output_format = 'json';  | 
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| 25 | |||
| 26 | |||
| 27 | /**  | 
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| 28 | * Possible output formats  | 
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| 29 | */  | 
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| 30 | const OUTPUT_FORMATS = ['json', 'xml', 'text'];  | 
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| 31 | |||
| 32 | |||
| 33 | /**  | 
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| 34 | * Human readable output  | 
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| 35 | *  | 
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| 36 | * @var bool  | 
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| 37 | */  | 
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| 38 | protected $pretty_format = false;  | 
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| 39 | |||
| 40 | |||
| 41 | /**  | 
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| 42 | * Headers  | 
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| 43 | *  | 
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| 44 | * @var array  | 
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| 45 | */  | 
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| 46 | protected $headers = [];  | 
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| 47 | |||
| 48 | |||
| 49 | /**  | 
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| 50 | * Code  | 
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| 51 | *  | 
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| 52 | * @var int  | 
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| 53 | */  | 
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| 54 | protected $code = 200;  | 
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| 55 | |||
| 56 | |||
| 57 | /**  | 
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| 58 | * Body  | 
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| 59 | *  | 
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| 60 | * @var string  | 
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| 61 | */  | 
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| 62 | protected $body;  | 
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| 63 | |||
| 64 | |||
| 65 | /**  | 
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| 66 | * body only  | 
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| 67 | *  | 
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| 68 | * @var bool  | 
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| 69 | */  | 
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| 70 | protected $body_only = false;  | 
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| 71 | |||
| 72 | |||
| 73 | /**  | 
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| 74 | * Init response  | 
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| 75 | *  | 
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| 76 | * @return void  | 
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| 77 | */  | 
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| 78 | public function __construct()  | 
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| 82 | |||
| 83 | |||
| 84 | /**  | 
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| 85 | * Set header  | 
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| 86 | *  | 
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| 87 | * @param string $header  | 
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| 88 | * @param string $value  | 
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| 89 | * @return Response  | 
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| 90 | */  | 
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| 91 | public function setHeader(string $header, string $value): Response  | 
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| 96 | |||
| 97 | |||
| 98 | /**  | 
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| 99 | * Get headers  | 
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| 100 | *  | 
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| 101 | * @return array  | 
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| 102 | */  | 
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| 103 | public function getHeaders(): array  | 
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| 107 | |||
| 108 | |||
| 109 | /**  | 
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| 110 | * Send headers  | 
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| 111 | *  | 
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| 112 | * @return Response  | 
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| 113 | */  | 
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| 114 | public function sendHeaders(): Response  | 
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| 122 | |||
| 123 | |||
| 124 | /**  | 
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| 125 | * Set response code  | 
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| 126 | *  | 
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| 127 | * @param int $code  | 
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| 128 | * @return Response  | 
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| 129 | */  | 
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| 130 | public function setCode(int $code): Response  | 
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| 139 | |||
| 140 | |||
| 141 | /**  | 
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| 142 | * Get response code  | 
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| 143 | *  | 
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| 144 | * @return int  | 
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| 145 | */  | 
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| 146 | public function getCode(): int  | 
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| 150 | |||
| 151 | |||
| 152 | /**  | 
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| 153 | * Set body  | 
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| 154 | *  | 
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| 155 | * @param mixed $body  | 
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| 156 | * @param bool $body_only  | 
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| 157 | * @return Response  | 
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| 158 | */  | 
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| 159 | public function setBody($body, bool $body_only = false): Response  | 
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| 165 | |||
| 166 | |||
| 167 | /**  | 
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| 168 | * Get body  | 
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| 169 | *  | 
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| 170 | * @return string  | 
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| 171 | */  | 
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| 172 | public function getBody()  | 
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| 176 | |||
| 177 | |||
| 178 | /**  | 
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| 179 | * Sends the actual response.  | 
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| 180 | *  | 
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| 181 | * @return void  | 
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| 182 | */  | 
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| 183 | public function send(): void  | 
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| 222 | |||
| 223 | |||
| 224 | /**  | 
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| 225 | * Get output format  | 
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| 226 | *  | 
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| 227 | * @return string  | 
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| 228 | */  | 
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| 229 | public function getOutputFormat(): string  | 
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| 233 | |||
| 234 | |||
| 235 | /**  | 
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| 236 | * Convert response to human readable output  | 
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| 237 | *  | 
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| 238 | * @param bool $format  | 
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| 239 | * @return Response  | 
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| 240 | */  | 
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| 241 | public function setPrettyFormat(bool $format): Response  | 
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| 246 | |||
| 247 | |||
| 248 | /**  | 
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| 249 | * Set header Content-Length $body.  | 
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| 250 | *  | 
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| 251 | * @param string $body  | 
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| 252 | * @return Response  | 
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| 253 | */  | 
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| 254 | public function setContentLength(string $body): Response  | 
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| 259 | |||
| 260 | |||
| 261 | /**  | 
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| 262 | * Converts $body to pretty json.  | 
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| 263 | *  | 
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| 264 | * @param mixed $body  | 
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| 265 | * @return string  | 
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| 266 | */  | 
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| 267 | public function asJSON($body): string  | 
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| 281 | |||
| 282 | |||
| 283 | /**  | 
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| 284 | * Converts mixed data to XML  | 
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| 285 | *  | 
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| 286 | * @param mixed $data  | 
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| 287 | * @param SimpleXMLElement $xml  | 
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| 288 | * @param string $child_name  | 
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| 289 | * @return string  | 
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| 290 | */  | 
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| 291 | public function toXML($data, Config $xml, string $child_name): string  | 
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| 307 | |||
| 308 | |||
| 309 | /**  | 
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| 310 | * Converts response to xml.  | 
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| 311 | *  | 
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| 312 | * @param mixed $body  | 
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| 313 | * @return string  | 
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| 314 | */  | 
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| 315 | public function asXML($body): string  | 
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| 328 | |||
| 329 | |||
| 330 | /**  | 
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| 331 | * Pretty formatted xml  | 
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| 332 | *  | 
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| 333 | * @param string $xml  | 
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| 334 | * @return string  | 
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| 335 | */  | 
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| 336 | public function prettyXml(string $xml): string  | 
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| 345 | |||
| 346 | |||
| 347 | /**  | 
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| 348 | * Set the current output format.  | 
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| 349 | *  | 
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| 350 | * @param string $format a key of $outputForms  | 
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| 351 | * @return Response  | 
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| 352 | */  | 
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| 353 | public function setOutputFormat(string $format): Response  | 
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| 358 | |||
| 359 | |||
| 360 | /**  | 
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| 361 | * Abort after response  | 
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| 362 | *  | 
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| 363 | * @return void  | 
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| 364 | */  | 
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| 365 | public function terminate(): void  | 
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| 369 | |||
| 370 | |||
| 371 | /**  | 
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| 372 | * Setup formats.  | 
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| 373 | *  | 
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| 374 | * @return Response  | 
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| 375 | */  | 
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| 376 | public function setupFormats(): Response  | 
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| 393 | }  | 
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| 394 | 
Adding a
@returnannotation to a constructor is not recommended, since a constructor does not have a meaningful return value.Please refer to the PHP core documentation on constructors.