class Configuration {

    public void setPersistentStorageDirectory(@Nullable String persistentStorageDirectory) {
        if (persistentStorageDirectory == null || persistentStorageDirectory.isEmpty()) {
            persistentStorageDirectory = System.getProperty("user.dir");
            if (persistentStorageDirectory == null || persistentStorageDirectory.isEmpty()) {
                throw new IllegalArgumentException("empty \"persistentStorageDirectory\" config and \"user.dir\" environment property");
            }
        }
        this.persistentStorageDirectory = persistentStorageDirectory;
    }

      Configuration();

}