@Override
public void open() throws DatabaseConfigurationException {
final File file = new File(getDataDir(), FILE_NAME);
LOG.debug("Creating '" + file.getName() + "'...");
try {
btree = new BTreeStore(pool, STRUCTURAL_INDEX_ID, false,
file, pool.getCacheManager(), DEFAULT_STRUCTURAL_KEY_THRESHOLD);
} catch (final DBException e) {
LOG.error("Failed to initialize structural index: " + e.getMessage(), e);
throw new DatabaseConfigurationException(e.getMessage(), e);
}