fixed possible null pointer

git-svn-id: http://svn.igniterealtime.org/svn/repos/messenger/trunk@1567 b35dd754-fafc-0310-a699-88a17e54d16e

src/plugins/search/src/web/advance-user-search.jsp

@@ -22,6 +22,7 @@
 
 	List<User> users = new ArrayList<User>();
 
+	if (criteria != null) {
 		for (String searchField : searchFields) {
 			
 			boolean searchValue = ParamUtils.getBooleanParameter(request, searchField, false);
@@ -37,6 +38,7 @@
 	            }
 	    		}
 		}
+	}
 %>
 <jsp:useBean id="pageinfo" scope="request" class="org.jivesoftware.admin.AdminPageBean"/>
 <%