code: public static AuthDescriptor typical(String u, String p) {
      return new AuthDescriptor(new String[] { "CRAM-MD5", "PLAIN" },
          new PlainCallbackHandler(u, p));
    }
docs: Get a typical auth descriptor for CRAM-MD5 or PLAIN auth with the given
  username and password.
  
  @param u the username
  @param p the password
  
  @return an AuthDescriptor