强大的PHP缓存种(eaccelerator、apc、xcache、memcache模块缓存)

cache_expire=$exp_time;
        $this->cache_params=$params;
        $this->setCacheType($type);
    }
     
    public function __destruct() {
        unset($this->cache_external);
    }
     
    // Prevent users to clone the instance
    public function __clone(){
        $this->cacheError('Clone is not allowed.');
    }
     
    //deletes cache from folder
    public function clearCache(){
        switch($this->cache_type){
            case 'eaccelerator':
                @eaccelerator_clean();
                @eaccelerator_clear();
            break;
 
            case 'apc':
                apc_clear_cache('user');
            break;
 
            case 'xcache':
                xcache_clear_cache(XC_TYPE_VAR, 0);
            break;
 
            case 'memcache':
                @$this->cache_external->flush();
            break;
             
            case 'filecache':
                $this->cache_external->deleteCache();
            break;
        }  
    }
     
    //writes or reads the cache
    public function cache($key, $value='',$ttl=''){
        if ($value!=''){//wants to write
            if ($ttl=='') $ttl=$this->cache_expire;
            $this->put($key, $value,$ttl);
        }
        else return $this->get($key);//reading value
    }
     
    //creates new cache files with the given data, $key== name of the cache, data the info/values to store
    private function put($key,$data,$ttl='' ){
        if ($ttl=='') $ttl=$this->cache_expire;
         
        switch($this->cache_type){
            case 'eaccelerator':
                eaccelerator_put($key, serialize($data), $ttl);
            break;
 
            case 'apc':
                apc_store($key, $data, $ttl);
            break;
 
            case 'xcache':
                xcache_set($key, serialize($data), $ttl);
            break;
 
            case 'memcache':
                $data=serialize($data);
                if (!$this->cache_external->replace($key, $data, false, $ttl))
                $this->cache_external->set($key, $data, false, $ttl);
            break;
             
            case 'filecache':
                $this->cache_external->cache($key,$data);
            break;
        }  
    }
     
    //returns cache for the given key
    private function get($key){
        switch($this->cache_type){
            case 'eaccelerator':
                $data =  @unserialize(eaccelerator_get($key));
            break;
 
            case 'apc':
                $data =  apc_fetch($key);
            break;
 
            case 'xcache':
                $data =  @unserialize(xcache_get($key));
            break;
 
            case 'memcache':
                $data = @unserialize($this->cache_external->get($key));
            break;
             
            case 'filecache':
                $data = $this->cache_external->cache($key);
            break;
        }  
        /*echo '
--returnning data for key:'.$key;
        var_dump($data);*/
        return $data;
    }
     
    //delete key from cache
    public function delete($key){
        switch($this->cache_type){
            case 'eaccelerator':
                eaccelerator_rm($key);
            break;
 
            case 'apc':
                apc_delete($key);
            break;
 
            case 'xcache':
                xcache_unset($key);
            break;
 
            case 'memcache':
                $this->cache_external->delete($key);
            break;
             
            case 'filecache':
                $this->cache_external->delete($key);
            break;
        }  
     
    }
    // Overloading for the Application variables and automatically cached
        public function __set($name, $value) {
            $this->put($name, $value, $this->cache_expire);
        }
     
        public function __get($name) {
            return $this->get($name);
        }
     
        public function __isset($key) {//echo "Is '$name' set?\n"
            if ($this->get($key) !== false)  return true;
            else return false;
        }
     
        public function __unset($name) {//echo "Unsetting '$name'\n";
            $this->delete($name);
        }
    //end overloads
     
    public function getCacheType(){
        return $this->$this->cache_type;
    }  
     
    //sets the cache if its installed if not triggers error
    public function setCacheType($type){
        $this->cache_type=strtolower($type);
         
        switch($this->cache_type){
            case 'eaccelerator':
                if (function_exists('eaccelerator_get')) $this->cache_type = 'eaccelerator';
                else $this->cacheError('eaccelerator not found');   
            break;
 
            case 'apc':
                if (function_exists('apc_fetch')) $this->cache_type = 'apc' ;
                else $this->cacheError('APC not found'); 
            break;
 
            case 'xcache':
                if (function_exists('xcache_get')) $this->cache_type = 'xcache' ;
                else $this->cacheError('Xcache not found');
            break;
 
            case 'memcache':
                if (class_exists('Memcache')) $this->init_memcache();
                else $this->cacheError('memcache not found');
            break;
             
            case 'filecache':
                if (class_exists('fileCache'))$this->init_filecache();
                else $this->cacheError('fileCache not found');
            break;
             
            case 'auto'://try to auto select a cache system
                if (function_exists('eaccelerator_get'))    $this->cache_type = 'eaccelerator';                                      
                elseif (function_exists('apc_fetch'))       $this->cache_type = 'apc' ;                                    
                elseif (function_exists('xcache_get'))      $this->cache_type = 'xcache' ;                                       
                elseif (class_exists('Memcache'))           $this->init_memcache();
                elseif (class_exists('fileCache'))          $this->init_filecache();
                else $this->cacheError('not any compatible cache was found');
            break;
             
            default://not any cache selected or wrong one selected
                if (isset($type)) $msg='Unrecognized cache type selected '.$type.'';
                else $msg='Not any cache type selected';
                $this->cacheError($msg);    
            break;
        }
    }  
         
    private function init_memcache(){//get instance of the memcache class
        if (is_array($this->cache_params)){
            $this->cache_type = 'memcache';
            $this->cache_external = new Memcache;
            foreach ($this->cache_params as $server) {
                $server['port'] = isset($server['port']) ? (int) $server['port'] : ini_get('memcache.default_port');
                $server['persistent'] = isset($server['persistent']) ? (bool) $server['persistent'] : true;
                $this->cache_external->addServer($server['host'], $server['port'], $server['persistent']);
            }
        }
        else $this->cacheError('memcache needs an array, example:
                    wrapperCache::GetInstance(\'memcache\',30,array(array(\'host\'=>\'localhost\')));');
    }
     
    private function init_filecache(){//get instance of the filecache class
        $this->cache_type = 'filecache';
        $this->cache_external = fileCache::GetInstance($this->cache_expire,$this->cache_params);
    }
     
    public function getAvailableCache($return_format='html'){//returns the available cache
        $avCaches   = array();
        $avCaches[] = array('eaccelerator',function_exists('eaccelerator_get'));                                      
        $avCaches[] = array('apc',function_exists('apc_fetch')) ;                                    
        $avCaches[] = array('xcache',function_exists('xcache_get'));                                       
        $avCaches[] = array('memcache',class_exists('Memcache'));
        $avCaches[] = array('fileCache',class_exists('fileCache'));
         
        if ($return_format=='html'){
            $ret='
';
            foreach ($avCaches as $c){
                $ret.='
'.$c[0].' - ';
                if ($c[1]) $ret.='Found/Compatible';
                else $ret.='Not Found/Incompatible';
                $ret.='';
            }
            return $ret.'
';
        }
        else return $avCaches; 
    }
     
    private function cacheError($msg){//triggers error
        trigger_error('
wrapperCache error: '.$msg.
                    '
If you want you can try with \'auto\' for auto select a compatible cache.
                    
Or choose a supported cache from list:'.$this->getAvailableCache(), E_USER_ERROR);
    }
}
?> 

?基于文件的