public IntervalBuilderLocatorImpl getIntervalBuilderLocatorImpl() { if (intervalBuilderLocator == null) { intervalBuilderLocator = new IntervalBuilderLocatorImpl( checkNotNull(getIntervalBuilderDynamicLabel(), "IntervalBuilderDynamicLabel"), checkNotNull(getIntervalBuilderDynamicDate(), "IntervalBuilderDynamicDateImpl"), checkNotNull(getIntervalBuilderFixedDate(), "IntervalBuilderFixedDate")); } return intervalBuilderLocator; }