abstract class etsis_Abstract_Cache
{

    abstract function read($key, $namespace);

    abstract function create($key, $data, $namespace, $ttl);

    abstract function delete($key, $namespace);
    
    abstract function flush();
    
    abstract function flushNamespace($namespace);
    
    abstract function set($key, $data, $namespace, $ttl);
    
    abstract function getStats();
    
    abstract function inc($key, $offset, $namespace);
    
    abstract function dec($key, $offset, $namespace);

    abstract protected function uniqueKey($key, $namespace);

    abstract protected function _exists($key, $namespace);
}