code: public void activateVersionControl(final String entryType, final Package converterPackage) throws CouldNotPerformException {
          if (!isEmpty()) {
              throw new CouldNotPerformException("Could not activate version control because registry already loaded! Please activate version control before loading the registry.");
          }
          versionControl = new DBVersionControl(entryType, fileProvider, converterPackage, databaseDirectory, this);
      }
docs: This method activates the version control unit of the underlying registry
  db. The version check and db upgrade is automatically performed during
  the registry db loading phrase. The db will be upgraded to the latest db
  format provided by the given converter package. The converter package
  should contain only classes implementing the DBVersionConverter
  interface. To fully support outdated db upgrade make sure that the
  converter pipeline covers the whole version range!
  <p>
  Activate version control before loading the registry. Please provide
  within the converter package only converter with the naming structure
  [$(EntryType)_$(VersionN)_To_$(VersionN+1)_DBConverter].
  <p>
  Example:
  <p>
  converter package myproject.db.converter containing the converter
  pipeline
  <p>
  myproject.db.converter.DeviceConfig_0_To_1_DBConverter.class
  myproject.db.converter.DeviceConfig_1_To_2_DBConverter.class
  myproject.db.converter.DeviceConfig_2_To_3_DBConverter.class
  <p>
  Would support the db upgrade from version 0 till the latest db version 3.
  
  @param entryType
  @param converterPackage the package containing all converter which
  provides db entry updates from the first to the latest db version.
  
  @throws CouldNotPerformException in case of an invalid converter pipeline
  or initialization issues.