diff --git a/nanolets/src/main/java/org/nanohttpd/router/RouterNanoHTTPD.java b/nanolets/src/main/java/org/nanohttpd/router/RouterNanoHTTPD.java
index 0a11c012..de949b0a 100644
--- a/nanolets/src/main/java/org/nanohttpd/router/RouterNanoHTTPD.java
+++ b/nanolets/src/main/java/org/nanohttpd/router/RouterNanoHTTPD.java
@@ -235,7 +235,7 @@ public Response get(UriResource uriResource, Map<String, String> urlParams, IHTT
                 try {
                     return Response.newChunkedResponse(getStatus(), getMimeTypeForFile(fileOrdirectory.getName()), fileToInputStream(fileOrdirectory));
                 } catch (IOException ioe) {
-                    return Response.newFixedLengthResponse(Status.REQUEST_TIMEOUT, "text/plain", null);
+                    return Response.newFixedLengthResponse(Status.REQUEST_TIMEOUT, "text/plain", (String) null);
                 }
             }
         }