code: protected void doTokenAuth(AuthToken token, HttpServletRequest request, HttpServletResponse response,
              FilterChain chain) throws IOException, ServletException {
          AuthPrincipal principal = new AuthPrincipal(token.getPrincipal());
          principal.addRoles(token.getRoles());
          doFilterChain(request, response, chain, principal);
      }
docs: Implements token based authentication.  This simply creates a principal from the {@link AuthToken}
  and then calls doFilterChain.
  @param token the token
  @param request the request
  @param response the response
  @param chain the filterchain
  @throws IOException when I/O failure occurs in filter chain
  @throws ServletException when servlet exception occurs during auth