code: public void flushSecurityDomainCache(String domain) throws Exception {
          Address addr = Address.root().add(SUBSYSTEM, SUBSYSTEM_SECURITY, SECURITY_DOMAIN, domain);
          ModelNode request = createRequest("flush-cache", addr);
          ModelNode result = execute(request);
          if (!isSuccess(result)) {
              log.warn("Flushing " + domain + " failed - principals may be longer cached than expected");
          }
      }
docs: send a :flush-cache operation to the passed security domain
  @param domain simple name of the domain
  @throws Exception any error