code: public void setCredentials(final String userId, final String apiToken, final String apiSecret) {
          if (userId != null && apiToken != null && apiSecret != null) {
              this.usersUri = String.format(BandwidthConstants.USERS_URI_PATH, userId.replaceAll(" ", ""));
              this.token = apiToken.replaceAll(" ", "");
              this.secret = apiSecret.replaceAll(" ", "");
  
              validateCredentials();
          } else {
              throw new MissingCredentialsException();
          }
      }
docs: The setCredentials() provides a convenience method to pass the userId, API-token and API-secret after
  a client has been instantiated.
  
  @param userId    the user id.
  @param apiToken  the API token.
  @param apiSecret the API secret.