分享:php文件缓存类

<?php 
/**
 * 文件缓存类
 * @author flynetcn
 * @site wwww.jbxue.com
 */ 
class FileCache 
{ 
    const CACHE_DIR = '/tmp/cache'; 
    private $dir; 
    private $expire = 300; 
 
    /**
     * @param $strDir 缓存子目录(方便清cache)
     */ 
    function __construct($strDir='') 
    { 
        if ($strDir) { 
            $this->dir = self::CACHE_DIR.'/'.$strDir; 
        } 
    } 
 
    private function getFileName($strKey) 
    { 
        return $this->dir.'/'.$strKey; 
    } 
 
    public function setExpire($intSecondNum) 
    { 
        if ($intSecondNum<10 || !is_int($intSecondNum)) { 
            return false; 
        } 
        $this->expire = $intSecondNum; 
        return true; 
    } 
 
    public function getExpire() 
    { 
        return $this->expire; 
    } 
 
    public function get($strKey) 
    { 
        $strFileName = $this->getFileName($strKey); 
        if (!@file_exists($strFileName)) { 
            return false; 
        } 
        if (filemtime($strFileName) < (time()-$this->expire)) { 
            return false; 
        } 
        $intFileSize = filesize($strFileName); 
        if ($intFileSize == 0) { 
            return false; 
        } 
        if (!$fp = @fopen($strFileName, 'rb')) { 
            return false; 
        } 
        flock($fp, LOCK_SH); 
        $cacheData = unserialize(fread($fp, $intFileSize)); 
        flock($fp, LOCK_UN); 
        fclose($fp); 
        return $cacheData; 
    } 
 
    public function set($strKey, $cacheData) 
    { 
        if (!is_dir($this->dir)) { 
            if (!@mkdir($this->dir, 0755, true)) { 
                trigger_error("mkdir({$this->dir}, 0755, true) failed", E_USER_ERROR); 
                return false; 
            } 
        } 
        $strFileName = $this->getFileName($strKey); 
        if (@file_exists($strFileName)) { 
            $intMtime = filemtime($strFileName); 
        } else { 
            $intMtime = 0; 
        } 
        if (!$fp = fopen($strFileName,'wb')) { 
            return false; 
        } 
        if (!flock($fp, LOCK_EX+LOCK_NB)) { 
            fclose($fp); 
            return false; 
        } 
        if (time() - $intMtime < 1) { 
            flock($fp, LOCK_UN); 
            fclose($fp); 
            return false; 
        } 
        fseek($fp, 0); 
        ftruncate($fp, 0); 
        fwrite($fp, serialize($cacheData)); 
        flock($fp, LOCK_UN); 
        fclose($fp); 
        @chmod($strFileName, 0755); 
        return true; 
    } 
}