public function __construct($expire = NULL, $stateFile = NULL, $oldMetadataSrc = NULL)
{
$this->expire = $expire;
$this->metadata = array();
$this->oldMetadataSrc = $oldMetadataSrc;
$this->stateFile = $stateFile;
$this->changed = FALSE;
// Read file containing $state from disk
if (is_readable($stateFile)) {
require $stateFile;
}
$this->state = isset($state) ? $state : array();
}