private void move(UserRingTable ringTable) {
private boolean move(UserRingTable ringTable) {
    private void move(UserRingTable ringTable) {        int step = -1;        Collection ids = ringTable.getRowsToMoveUp();        if (null == ids) {            step = 1;            ids = ringTable.getRowsToMoveDown();            if (null == ids) {                // nothing to do                return;            }        }        CallGroup callGroup = getCallGroup();        callGroup.moveRings(ids, step);    }