code: private CheckoutState getCheckoutState(final AckCodeType ack) {
  
  		switch (ack) {
  
  			case CUSTOMCODE:
  				return CheckoutState.Custom;
  
  			case FAILURE:
  				return CheckoutState.Failure;
  
  			case FAILUREWITHWARNING:
  				return CheckoutState.FailureWithWarning;
  
  			case PARTIALSUCCESS:
  				return CheckoutState.PartialSuccess;
  
  			case SUCCESS:
  				return CheckoutState.Success;
  
  			case SUCCESSWITHWARNING:
  				return CheckoutState.SuccessWithWarning;
  
  			case WARNING:
  				return CheckoutState.Warning;
  		}
  
  		return null;
  	}
docs: ----- private methods -----