}

    @Override
    public synchronized <T> DefaultServiceLocator.ServiceFactory<T> findFactory(Class<T> serviceType) {
        if (serviceFactories.containsKey(serviceType)) {
            return Cast.uncheckedCast(serviceFactories.get(serviceType));
        }
        DefaultServiceLocator.ServiceFactory<T> factory = delegate.findFactory(serviceType);
        serviceFactories.put(serviceType, factory);
        return factory;
    }

    <T> DefaultServiceLocator.ServiceFactory<T> getFactory(Class<T> serviceType) throws UnknownServiceException;

    @Nullable
    <T> DefaultServiceLocator.ServiceFactory<T> findFactory(Class<T> serviceType);