/**
  * Obtains the (unmodifiable) set of {@link DataStoreConfiguration} instances that will be used by
  * uniVocity to instantiate the data stores manipulated by this engine.
  *
  * @return the configurations of all data stores whose entities will be mapped using the engine
  *     created by this class
  */
 public final Set<DataStoreConfiguration> getDataStoreConfigurations() {
   return Collections.unmodifiableSet(dataStoreConfigurations);
 }
 /**
  * Obtains the (unmodifiable) set of {@link CustomDataStoreFactory} instances that should be used
  * by uniVocity to read any custom {@link DataStoreConfiguration} to properly create instances of
  * {@link CustomDataStore}.
  *
  * @return the factories that process user-provided data store configurations and generate custom
  *     data store instances.
  */
 public final Set<CustomDataStoreFactory<?>> getCustomDataStoreFactories() {
   return Collections.unmodifiableSet(customDataStoreFactories);
 }