private synchronized void deleteAllProperties(final Map<String,String> originalMap) {
        Connection con = null;
        PreparedStatement pstmt = null;
        try {
            con = DbConnectionManager.getConnection();
            pstmt = con.prepareStatement(DELETE_ALL_PROPERTIES);
            pstmt.setString(1, group.getName());
            pstmt.executeUpdate();
        }
        catch (SQLException e) {
            logger.error(e.getMessage(), e);
        }
        finally {
            DbConnectionManager.closeConnection(pstmt, con);
        }

        // Clean up caches.
        DefaultGroupProvider.sharedGroupMetaCache.clear();
        GroupManager.getInstance().propertiesDeletedPostProcess(group, originalMap);
    }
Delete all properties from the database for the current group

@param originalMap The properties of the group prior to the removal.
xmppserver/src/main/java/org/jivesoftware/openfire/group/DefaultGroupPropertyMap.java