Complex classes like AdapterFileAbstract 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 AdapterFileAbstract, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 10 | abstract class AdapterFileAbstract implements iAdapter  | 
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| 11 | { | 
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| 12 | const CACHE_FILE_PREFIX = '__';  | 
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| 13 | |||
| 14 | const CACHE_FILE_SUBFIX = '.php.cache';  | 
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| 15 | |||
| 16 | /**  | 
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| 17 | * @var bool  | 
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| 18 | */  | 
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| 19 | public $installed = false;  | 
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| 20 | |||
| 21 | /**  | 
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| 22 | * @var string  | 
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| 23 | */  | 
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| 24 | protected $cacheDir;  | 
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| 25 | |||
| 26 | /**  | 
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| 27 | * @var iSerializer  | 
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| 28 | */  | 
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| 29 | protected $serializer;  | 
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| 30 | |||
| 31 | /**  | 
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| 32 | * @var string  | 
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| 33 | */  | 
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| 34 | protected $fileMode = '0755';  | 
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| 35 | |||
| 36 | /**  | 
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| 37 | * @param callable|string|null $cacheDir  | 
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| 38 | */  | 
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| 39 | 34 | public function __construct($cacheDir = null)  | 
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| 57 | |||
| 58 | /**  | 
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| 59 | * Recursively creates & chmod directories.  | 
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| 60 | *  | 
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| 61 | * @param string $path  | 
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| 62 | *  | 
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| 63 | * @return bool  | 
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| 64 | */  | 
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| 65 | 34 | protected function createCacheDirectory($path): bool  | 
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| 111 | |||
| 112 | /**  | 
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| 113 | * @param string $cacheFileWithPath  | 
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| 114 | *  | 
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| 115 | * @return bool  | 
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| 116 | */  | 
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| 117 | 12 | protected function deleteFile($cacheFileWithPath): bool  | 
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| 125 | |||
| 126 | /**  | 
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| 127 |      * {@inheritdoc} | 
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| 128 | */  | 
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| 129 | 6 | public function exists(string $key): bool  | 
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| 135 | |||
| 136 | /**  | 
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| 137 |      * {@inheritdoc} | 
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| 138 | */  | 
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| 139 | abstract public function get(string $key);  | 
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| 140 | |||
| 141 | /**  | 
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| 142 |      * {@inheritdoc} | 
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| 143 | */  | 
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| 144 | 1 | public function installed(): bool  | 
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| 148 | |||
| 149 | /**  | 
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| 150 |      * {@inheritdoc} | 
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| 151 | */  | 
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| 152 | 12 | public function remove(string $key): bool  | 
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| 158 | |||
| 159 | /**  | 
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| 160 |      * {@inheritdoc} | 
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| 161 | */  | 
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| 162 | 3 | public function removeAll(): bool  | 
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| 177 | |||
| 178 | /**  | 
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| 179 |      * {@inheritdoc} | 
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| 180 | */  | 
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| 181 | 9 | public function set(string $key, $value): bool  | 
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| 185 | |||
| 186 | /**  | 
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| 187 |      * {@inheritdoc} | 
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| 188 | */  | 
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| 189 | abstract public function setExpired(string $key, $value, int $ttl = 0): bool;  | 
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| 190 | |||
| 191 | /**  | 
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| 192 | * @param string $key  | 
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| 193 | *  | 
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| 194 | * @return string  | 
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| 195 | */  | 
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| 196 | 16 | protected function getFileName(string $key): string  | 
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| 200 | |||
| 201 | /**  | 
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| 202 | * Set the file-mode for new cache-files.  | 
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| 203 | *  | 
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| 204 | * e.g. '0777', or '0755' ...  | 
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| 205 | *  | 
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| 206 | * @param string $fileMode  | 
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| 207 | */  | 
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| 208 | public function setFileMode($fileMode)  | 
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| 212 | |||
| 213 | /**  | 
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| 214 | * @param int $ttl  | 
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| 215 | *  | 
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| 216 | * @return bool  | 
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| 217 | */  | 
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| 218 | 22 | protected function ttlHasExpired(int $ttl): bool  | 
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| 226 | |||
| 227 | /**  | 
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| 228 | * @param mixed $data  | 
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| 229 | *  | 
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| 230 | * @return bool  | 
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| 231 | */  | 
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| 232 | 22 | protected function validateDataFromCache($data): bool  | 
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| 246 | |||
| 247 | /**  | 
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| 248 | * copy&past from https://github.com/webimpress/safe-writer (thx @michalbundyra)  | 
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| 249 | *  | 
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| 250 | * @param string $file  | 
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| 251 | * @param string $content  | 
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| 252 | * @param int|null $chmod  | 
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| 253 | *  | 
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| 254 | * @return bool  | 
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| 255 | */  | 
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| 256 | 21 | protected function writeFile($file, $content, $chmod = null): bool  | 
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| 298 | }  | 
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| 299 |