private boolean isUsernameRegistered(JiraClient client, String username) {
    for (RemoteUser user : client.searchUser(username)) {
      if (user.getName().equalsIgnoreCase(username)) {
        return true;
      }
    }

    return false;
  }
  private boolean isEmailAddressRegistered(JiraClient client, String email) {
    for (RemoteUser user : client.searchUser(email)) {
      if (user.getEmail().equalsIgnoreCase(email)) {
        return true;
      }
    }

    return false;
  }
  @JavaScriptMethod
  public RemoteUser[] getExistingUsers(String jiraConfigName, String query) {
    JiraSession session = getJiraSession(getJiraConfig(jiraConfigName));
    JiraClient client = new JiraClient(session);

    RemoteUser[] users = client.searchUser(query);

    session.close();
    return users;
  }