Forgot an instanceof check in the URLHandlers

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@728289 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/framework/src/main/java/org/apache/felix/framework/URLHandlers.java b/framework/src/main/java/org/apache/felix/framework/URLHandlers.java
index a0be37c..07951f0 100644
--- a/framework/src/main/java/org/apache/felix/framework/URLHandlers.java
+++ b/framework/src/main/java/org/apache/felix/framework/URLHandlers.java
@@ -478,14 +478,22 @@
         {
             for (Iterator iter = m_streamHandlerCache.values().iterator();iter.hasNext();)
             {
-                ((URLHandlersStreamHandlerProxy) iter.next()).flush();
+                Object proxy = iter.next();
+                if (proxy instanceof URLHandlersStreamHandlerProxy)
+                {
+                    ((URLHandlersStreamHandlerProxy) proxy).flush();
+                }
             }
         }
         if (m_contentHandlerCache != null)
         {
             for (Iterator iter = m_contentHandlerCache.values().iterator();iter.hasNext();)
             {
-                ((URLHandlersContentHandlerProxy) iter.next()).flush();
+                Object proxy = iter.next();
+                if (proxy instanceof URLHandlersContentHandlerProxy)
+                {
+                    ((URLHandlersContentHandlerProxy) proxy).flush();
+                }
             }
         }
     }