diff --git a/screening/source/java/ch/systemsx/cisd/openbis/dss/generic/server/ImageGenerationDescriptionFactory.java b/screening/source/java/ch/systemsx/cisd/openbis/dss/generic/server/ImageGenerationDescriptionFactory.java
index 9a4ac8162e4871eecb680007d39a1e63e205840e..6e72df4710b3a7cc377b37f1460c343f1102f654 100644
--- a/screening/source/java/ch/systemsx/cisd/openbis/dss/generic/server/ImageGenerationDescriptionFactory.java
+++ b/screening/source/java/ch/systemsx/cisd/openbis/dss/generic/server/ImageGenerationDescriptionFactory.java
@@ -100,7 +100,7 @@ class ImageGenerationDescriptionFactory
             HttpServletRequest request)
     {
         Map<String, List<String>> datasetToChannelsMap = new HashMap<String, List<String>>();
-        Enumeration params = request.getParameterNames();
+        Enumeration<?> params = request.getParameterNames();
         while (params.hasMoreElements())
         {
             String paramName = (String) params.nextElement();