code: public void generateAesKeys(int numKeys, int startOffset) throws IOException, KeyStoreException {
      for (int i = 1; i <= numKeys; i++) {
        SecretKey key = generateKey();
        ks.setEntry(String.valueOf(i + startOffset), new KeyStore.SecretKeyEntry(key),
            new KeyStore.PasswordProtection(password));
      }
  
      saveKeystore();
    }
docs: Generate a set of AES keys for the store. The key ids will simple be (startOffset ... startOffset + numKeys).
  @param numKeys Number of keys to generate
  @param startOffset ID to start generating keys with
  @throws IOException If there is an error serializing the keystore back to disk
  @throws KeyStoreException If there is an error serializing the keystore back to disk