+
+ /**
+ * Prepends backPath to given URL if it's not an absolute URL
+ *
+ * @param string $url
+ * @return string
+ */
+ private function prependBackPath($url) {
+ if (strpos($url, '://') !== FALSE || substr($url, 0, 1) === '/') {
+ return $url;
+ } else {
+ return $this->backPath . $url;
+ }
+
+ }