Source for file CachedObjectStorageFactory.php
Documentation is available at CachedObjectStorageFactory.php 
    const cache_in_memory                =  'Memory';  
    const cache_in_memory_gzip            =  'MemoryGZip';  
    const cache_in_memory_serialized    =  'MemorySerialized';  
    const cache_to_discISAM                =  'DiscISAM';  
    const cache_to_apc                    =  'APC';  
    const cache_to_memcache                =  'Memcache';  
    const cache_to_phpTemp                =  'PHPTemp';  
    const cache_to_wincache                =  'Wincache';  
    private static $_cacheStorageMethod =  null;  
    private static $_cacheStorageClass =  null;  
    private static $_storageMethods =  array(  
        self::cache_in_memory_gzip,  
        self::cache_in_memory_serialized,  
    private static $_storageMethodDefaultParameters =  array(  
        self::cache_in_memory                =>  array(  
        self::cache_in_memory_gzip            =>  array(  
        self::cache_in_memory_serialized    =>  array(  
        self::cache_to_phpTemp                =>  array( 'memoryCacheSize'    =>  '1MB'  
        self::cache_to_discISAM                =>  array(  
        self::cache_to_apc                    =>  array( 'cacheTime'        =>  600  
        self::cache_to_memcache                =>  array( 'memcacheServer'    =>  'localhost',  
        self::cache_to_wincache                =>  array( 'cacheTime'        =>  600  
    private static $_storageMethodParameters =  array();  
        if (!is_null(self::$_cacheStorageMethod)) {  
            return self::$_cacheStorageMethod;  
    }    //    function getCacheStorageMethod()  
        if (!is_null(self::$_cacheStorageClass)) {  
            return self::$_cacheStorageClass;  
    }    //    function getCacheStorageClass()  
        return self::$_storageMethods;  
    }    //    function getCacheStorageMethods()  
    public static function initialize($method =  self::cache_in_memory, $arguments =  array()) {  
        if (!in_array($method,self::$_storageMethods)) {  
            case self::cache_to_apc    :   
                if (apc_sma_info() ===  false) {  
            case self::cache_to_memcache :   
            case self::cache_to_wincache :   
        self::$_storageMethodParameters[$method] =  self::$_storageMethodDefaultParameters[$method];  
        foreach($arguments as $k =>  $v) {  
            if (isset (self::$_storageMethodParameters[$method][$k])) {  
                self::$_storageMethodParameters[$method][$k] =  $v;  
        if (is_null(self::$_cacheStorageMethod)) {  
            self::$_cacheStorageClass =  'PHPExcel_CachedObjectStorage_'. $method;  
            self::$_cacheStorageMethod =  $method;  
    }    //    function initialize()  
    public static function getInstance(PHPExcel_Worksheet $parent) {  
        if (is_null(self::$_cacheStorageMethod)) {  
        $instance =  new self::$_cacheStorageClass($parent,self::$_storageMethodParameters[self::$_cacheStorageMethod]);  
        if (!is_null($instance)) {  
    }    //    function getInstance()  
 
 
        
       |