fix of NPE

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/trunk@11792 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/openfire/security/DefaultSecurityAuditProvider.java

@@ -124,13 +124,7 @@ public class DefaultSecurityAuditProvider implements SecurityAuditProvider {
         try {
             con = DbConnectionManager.getConnection();
             pstmt = DbConnectionManager.createScrollablePreparedStatement(con, sql);
-            rs = pstmt.executeQuery();
-            if (skipEvents != null) {
-                DbConnectionManager.scrollResultSet(rs, skipEvents);
-            }
-            if (numEvents != null) {
-                DbConnectionManager.setFetchSize(rs, numEvents);
-            }
+            
             int i = 1;
             if (username != null) {
                 pstmt.setString(i, username);
@@ -143,6 +137,15 @@ public class DefaultSecurityAuditProvider implements SecurityAuditProvider {
             if (endTime != null) {
                 pstmt.setLong(i, endTime.getTime());
             }
+            
+            rs = pstmt.executeQuery();
+            if (skipEvents != null) {
+                DbConnectionManager.scrollResultSet(rs, skipEvents);
+            }
+            if (numEvents != null) {
+                DbConnectionManager.setFetchSize(rs, numEvents);
+            }
+            
             int count = 0;
             while (rs.next() && count < numEvents) {
                 SecurityAuditEvent event = new SecurityAuditEvent();