public void save(List<ApiKey> storedKeys, OutputStream stream) throws IOException { if (storedKeys != null) { try (BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(stream, Util.createDefaultFileCharset()))) { for (ApiKey key : storedKeys) { writer.write(String.valueOf(key.getKeyId())); writer.write(DELIMITER); writer.write(key.getVerificationString()); writer.write("\n"); } logger.log(Level.INFO, "saved {0} api keys.", storedKeys.size()); writer.flush(); } } }