update

src/main/java/edu/umd/dawn/common/interceptor/RequestInterceptor.java

@@ -65,8 +65,12 @@ public class RequestInterceptor implements HandlerInterceptor {
             }
         }
 
-        Map<String, String> pathParams = (Map<String, String>)request.getAttribute(HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE);
-        pathParams.forEach((k, v) -> parameters.merge(k, v, String::concat));
+        Object p = request.getAttribute(HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE);
+
+        if (p != null) {
+            Map<String, String> pathParams = (Map<String, String>)p;
+            pathParams.forEach((k, v) -> parameters.merge(k, v, String::concat));
+        }
 
         return parameters;
     }