code: public void startCharging(String subscriptionId, String serviceContextId) throws Exception {
      // Initialize timers
      sendUpdatetimer =  new Timer();
      sendTerminateTimer =  new Timer();
      callDurationTimer =  new Timer();
  
      if(logger.isInfoEnabled()) {
        logger.info("(((o))) SERVICE HAS BEEN ESTABLISHED (((o)))");
      }
  
      // Start call time counter
      setCountCallTime(serviceContextId, 1000);
  
      // Check whether we should do new charging or terminate on final units.
      if(areFinalUnits) {
        setTerminateTimer(subscriptionId, serviceContextId, reservedUnits * 1000);
      }
      else {
        setUpdateTimer(subscriptionId, serviceContextId, reservedUnits * 1000);
      }
    }
docs: /* (non-Javadoc)
  @see org.mobicents.diameter.simulator.clients.RoClient#startAccounting(java.lang.String)