| 1 | <?php |
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| 5 | abstract class Compressor |
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| 6 | { |
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| 7 | /* @string compression level*/ |
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| 8 | protected $level = null; |
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| 9 | |||
| 10 | abstract public function getCompressorCommand(); |
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| 11 | |||
| 12 | /** |
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| 13 | * get the extension of the compressed file. |
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| 14 | * |
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| 15 | * @returns string |
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| 16 | */ |
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| 17 | public function getExtension() |
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| 21 | |||
| 22 | /** |
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| 23 | * Set compression level. |
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| 24 | * |
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| 25 | * @param string $level |
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| 26 | */ |
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| 27 | public function setLevel(string $level) |
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| 31 | } |
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| 32 |
In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code:
Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: