--- a/jaxp/src/java.xml/share/classes/javax/xml/catalog/CatalogResolverImpl.java	Tue Aug 30 17:49:43 2016 -0700
+++ b/jaxp/src/java.xml/share/classes/javax/xml/catalog/CatalogResolverImpl.java	Wed Aug 31 14:33:23 2016 -0700
@@ -119,6 +119,10 @@
         String result = null;
         CatalogImpl c = (CatalogImpl)catalog;
         String uri = Normalizer.normalizeURI(href);
+        if (uri == null) {
+            return null;
+        }
+
         //check whether uri is an urn
         if (uri != null && uri.startsWith(Util.URN)) {
             String publicId = Normalizer.decodeURN(uri);