code: @Override
      public void store(OAuthToken token, String envKey) {
          FileOutputStream fileOut;
          try {
              fileOut = new FileOutputStream(getFilePath(envKey));
              ObjectOutputStream out = new ObjectOutputStream(fileOut);
              out.writeObject(token);
              out.close();
              fileOut.close();
          } catch (Exception ex) {
              Logger.getLogger(FileStorageStrategy.class.getName()).log(Level.SEVERE, null, ex);
          }
      }
docs: Stores authorization token passed as an argument.
  @param token Token instance to be stored.
  @param envKey Environment key for token.