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:
Complex classes like Cron 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 Cron, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 8 | class Cron |
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| 9 | { |
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| 10 | /** |
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| 11 | * Weekday look-up table |
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| 12 | * |
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| 13 | * @var array |
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| 14 | */ |
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| 15 | protected static $weekdays = [ |
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| 16 | 'sun' => 0, |
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| 17 | 'mon' => 1, |
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| 18 | 'tue' => 2, |
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| 19 | 'wed' => 3, |
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| 20 | 'thu' => 4, |
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| 21 | 'fri' => 5, |
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| 22 | 'sat' => 6 |
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| 23 | ]; |
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| 24 | |||
| 25 | /** |
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| 26 | * Month name look-up table |
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| 27 | * |
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| 28 | * @var array |
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| 29 | */ |
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| 30 | protected static $months = [ |
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| 31 | 'jan' => 1, |
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| 32 | 'feb' => 2, |
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| 33 | 'mar' => 3, |
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| 34 | 'apr' => 4, |
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| 35 | 'may' => 5, |
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| 36 | 'jun' => 6, |
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| 37 | 'jul' => 7, |
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| 38 | 'aug' => 8, |
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| 39 | 'sep' => 9, |
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| 40 | 'oct' => 10, |
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| 41 | 'nov' => 11, |
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| 42 | 'dec' => 12 |
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| 43 | ]; |
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| 44 | |||
| 45 | /** |
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| 46 | * Value boundaries |
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| 47 | * |
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| 48 | * @var array |
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| 49 | */ |
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| 50 | protected static $boundaries = [ |
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| 51 | 0 => [ |
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| 52 | 'min' => 0, |
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| 53 | 'max' => 59 |
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| 54 | ], |
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| 55 | 1 => [ |
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| 56 | 'min' => 0, |
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| 57 | 'max' => 23 |
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| 58 | ], |
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| 59 | 2 => [ |
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| 60 | 'min' => 1, |
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| 61 | 'max' => 31 |
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| 62 | ], |
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| 63 | 3 => [ |
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| 64 | 'min' => 1, |
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| 65 | 'max' => 12 |
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| 66 | ], |
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| 67 | 4 => [ |
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| 68 | 'min' => 0, |
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| 69 | 'max' => 7 |
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| 70 | ] |
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| 71 | ]; |
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| 72 | |||
| 73 | /** |
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| 74 | * Cron expression |
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| 75 | * |
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| 76 | * @var string |
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| 77 | */ |
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| 78 | protected $expression; |
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| 79 | |||
| 80 | /** |
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| 81 | * Time zone |
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| 82 | * |
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| 83 | * @var \DateTimeZone |
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| 84 | */ |
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| 85 | protected $timeZone; |
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| 86 | |||
| 87 | /** |
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| 88 | * Matching register |
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| 89 | * |
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| 90 | * @var array|null |
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| 91 | */ |
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| 92 | protected $register; |
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| 93 | |||
| 94 | /** |
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| 95 | * Class constructor sets cron expression property |
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| 96 | * |
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| 97 | * @param string $expression cron expression |
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| 98 | * @param \DateTimeZone $timeZone |
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| 99 | */ |
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| 100 | 89 | public function __construct($expression = '* * * * *', \DateTimeZone $timeZone = null) |
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| 105 | |||
| 106 | /** |
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| 107 | * Set expression |
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| 108 | * |
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| 109 | * @param string $expression |
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| 110 | * @return self |
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| 111 | */ |
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| 112 | 89 | public function setExpression($expression) |
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| 119 | |||
| 120 | /** |
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| 121 | * Set time zone |
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| 122 | * |
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| 123 | * @param \DateTimeZone $timeZone |
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| 124 | * @return self |
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| 125 | */ |
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| 126 | 89 | public function setTimeZone(\DateTimeZone $timeZone = null) |
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| 131 | |||
| 132 | /** |
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| 133 | * Calculate next matching timestamp |
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| 134 | * |
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| 135 | * @param mixed $dtime \DateTime object, timestamp or null |
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| 136 | * @return int|bool next matching timestamp, or false on error |
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| 137 | */ |
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| 138 | 7 | public function getNext($dtime = null) |
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| 165 | |||
| 166 | /** |
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| 167 | * @param \DateTime $dtime |
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| 168 | * @param array $pointer |
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| 169 | * @return array |
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| 170 | */ |
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| 171 | 7 | private function adjust(\DateTime $dtime, array &$pointer) |
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| 172 | { |
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| 173 | 7 | $current = sscanf($dtime->format('i G j n Y w'), '%d %d %d %d %d %d'); |
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| 174 | |||
| 175 | switch (true) { |
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| 176 | 7 | View Code Duplication | case ($pointer[1] !== $current[1]): |
| 177 | 4 | $pointer[1] = $current[1]; |
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| 178 | 4 | $dtime->setTime($current[1], 0); |
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| 179 | 4 | break; |
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| 180 | |||
| 181 | 7 | View Code Duplication | case ($pointer[0] !== $current[0]): |
| 182 | 5 | $pointer[0] = $current[0]; |
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| 183 | 5 | $dtime->setTime($current[1], $current[0]); |
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| 184 | 5 | break; |
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| 185 | |||
| 186 | 7 | View Code Duplication | case ($pointer[4] !== $current[4]): |
| 187 | 1 | $pointer[4] = $current[4]; |
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| 188 | 1 | $dtime->setDate($current[4], 1, 1); |
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| 189 | 1 | $dtime->setTime(0, 0); |
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| 190 | 1 | break; |
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| 191 | |||
| 192 | 7 | View Code Duplication | case ($pointer[3] !== $current[3]): |
| 193 | 2 | $pointer[3] = $current[3]; |
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| 194 | 2 | $dtime->setDate($current[4], $current[3], 1); |
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| 195 | 2 | $dtime->setTime(0, 0); |
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| 196 | 2 | break; |
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| 197 | |||
| 198 | 7 | View Code Duplication | case ($pointer[2] !== $current[2]): |
| 199 | 2 | $pointer[2] = $current[2]; |
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| 200 | 2 | $dtime->setTime(0, 0); |
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| 201 | 2 | break; |
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| 202 | } |
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| 203 | |||
| 204 | 7 | return $current; |
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| 205 | } |
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| 206 | |||
| 207 | /** |
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| 208 | * @param \DateTime $dtime |
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| 209 | * @param array $current |
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| 210 | * @return bool |
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| 211 | */ |
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| 212 | 7 | private function forward(\DateTime $dtime, array $current) |
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| 232 | |||
| 233 | /** |
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| 234 | * Parse and validate cron expression |
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| 235 | * |
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| 236 | * @return bool true if expression is valid, or false on error |
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| 237 | */ |
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| 238 | 88 | public function isValid() |
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| 252 | |||
| 253 | /** |
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| 254 | * Match current or given date/time against cron expression |
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| 255 | * |
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| 256 | * @param mixed $dtime \DateTime object, timestamp or null |
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| 257 | * @return bool |
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| 258 | */ |
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| 259 | 82 | public function isMatching($dtime = null) |
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| 278 | |||
| 279 | /** |
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| 280 | * @param array $segments |
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| 281 | * @return bool |
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| 282 | * @throws \Exception |
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| 283 | */ |
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| 284 | 82 | private function match(array $segments) |
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| 297 | |||
| 298 | /** |
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| 299 | * Parse whole cron expression |
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| 300 | * |
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| 301 | * @return array |
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| 302 | * @throws \Exception |
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| 303 | */ |
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| 304 | 89 | private function parse() |
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| 322 | |||
| 323 | /** |
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| 324 | * Parse one segment of a cron expression |
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| 325 | * |
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| 326 | * @param int $index |
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| 327 | * @param string $segment |
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| 328 | * @param array $register |
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| 329 | * @throws \Exception |
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| 330 | */ |
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| 331 | 85 | private function parseSegment($index, array &$register, $segment) |
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| 346 | |||
| 347 | /** |
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| 348 | * @param int $index |
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| 349 | * @param array $register |
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| 350 | * @param string $element |
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| 351 | * @throws \Exception |
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| 352 | */ |
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| 353 | 85 | private function parseElement($index, array &$register, $element) |
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| 373 | |||
| 374 | /** |
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| 375 | * Parse range of values, e.g. "5-10" |
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| 376 | * |
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| 377 | * @param int $index |
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| 378 | * @param array $register |
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| 379 | * @param string $range |
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| 380 | * @param int $stepping |
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| 381 | * @throws \Exception |
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| 382 | */ |
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| 383 | 78 | private function parseRange($index, array &$register, $range, $stepping) |
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| 395 | |||
| 396 | /** |
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| 397 | * Parse stepping notation, e.g. "5-10/2" => 2 |
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| 398 | * |
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| 399 | * @param int $index |
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| 400 | * @param string $element |
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| 401 | * @param int $stepping |
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| 402 | * @throws \Exception |
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| 403 | */ |
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| 404 | 41 | private function parseStepping($index, &$element, &$stepping) |
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| 413 | |||
| 414 | /** |
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| 415 | * Validate whether a given range of values exceeds allowed value boundaries |
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| 416 | * |
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| 417 | * @param int $index |
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| 418 | * @param array $range |
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| 419 | * @return array |
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| 420 | * @throws \Exception |
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| 421 | */ |
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| 422 | 44 | private function validateRange($index, array $range) |
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| 434 | /** |
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| 435 | * @param int $index |
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| 436 | * @param int $value |
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| 437 | * @throws \Exception |
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| 438 | */ |
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| 439 | 65 | private function validateValue($index, $value) |
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| 450 | |||
| 451 | /** |
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| 452 | * @param int $index |
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| 453 | * @param array $segments |
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| 454 | * @throws \Exception |
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| 455 | */ |
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| 456 | 41 | private function validateStepping($index, array $segments) |
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| 466 | |||
| 467 | /** |
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| 468 | * @param int $index |
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| 469 | * @param array $register |
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| 470 | * @param array $range |
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| 471 | * @param int $stepping |
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| 472 | */ |
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| 473 | 73 | private function fillRegister($index, array &$register, array $range, $stepping) |
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| 485 | |||
| 486 | /** |
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| 487 | * @param int $index |
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| 488 | * @param array $register |
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| 489 | * @param array $range |
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| 490 | * @param int $value |
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| 491 | */ |
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| 492 | 29 | private function fillRegisterAcrossBoundaries($index, array &$register, $range, $value) |
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| 498 | |||
| 499 | /** |
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| 500 | * @param int $index |
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| 501 | * @param array $register |
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| 502 | * @param array $range |
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| 503 | * @param int $value |
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| 504 | */ |
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| 505 | 72 | private function fillRegisterBetweenBoundaries($index, array &$register, $range, $value) |
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| 511 | } |
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| 512 |
You can fix this by adding a namespace to your class:
When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries.