protected function composeKey($key)
    {
        $key = !$this->keyPrefix ? $key : $this->keyPrefix.$key;
        return $key;
    }
protected function composeKey($key)
    {
        $key = !$this->keyPrefix ? $key : $this->keyPrefix.$key;
        return $key;
    }
protected function composeKey ( $ key ) { $ key = ! $ this -> keyPrefix ? $ key : $ this -> keyPrefix . $ key ; return $ key ; }
Build the key if a domain or namespace was set.

@param string $key

@return string
Build the key if a domain or namespace was set .