TariffTreeSet tts = cm.getRealtimeTariffTreeSet( c.getId(), new GregorianCalendar(), "ipn", this.mid, true );

if(tts!=null){
List<TariffModuleTree> treeList = tts.getTreeList(new GregorianCalendar());
for (TariffModuleTree tree : treeList){
if (tree != null){
try {
TariffRequest req = new TariffRequest();
req.setRequestParam("action", "calculate");
req.setRequestParam("cid", new Integer(c.getId()));
req.setRequestParam("time", new GregorianCalendar());
req.setRequestParam("sid", new Integer(this.request_sid));
req.setRequestParam("amount", new Long(1L));
req.setRequestParam("tariffOptions", ContractTariffOptionDao.getContractRealtimeTariffOptionList(this.conSlave ,c.getId() ,new Date()));//c.getTariffOptions());

tree.processRequest(req);

if (req.wasAccepted())
{
...