public function execute(Request $request)
 {
     if (LOGGING) {
         Log::log(LoggingConstants::DEBUG, "commandmessage " . $this->operation . " operation");
     }
     /*Object*/
     $returnValue = null;
     if ($this->operation == "0") {
         /*IDestination*/
         $destObj = ORBConfig::getInstance()->getDataServices()->getDestinationManager()->getDestination($this->destination);
         /*Hashtable*/
         $headers = array();
         if ($destObj != null) {
             /*String*/
             $selectorName = $this->headers["DSSelector"];
             /*String*/
             $subtopic = $this->headers["DSSubtopic"];
             /*String*/
             $dsId = $this->headers["DSId"];
             /*Subscriber*/
             $subscriber = new Subscriber($selectorName, $destObj);
             $subscriber->setDSId($dsId);
             $subscriber->setSubtopic($subtopic);
             $guid = new GUID();
             $subscriber->setClientId($guid->toString());
             SubscriptionsManager::getInstance()->addSubscriber($dsId, $subscriber);
             $destObj->getServiceHandler()->handleSubscribe($subscriber);
         } else {
             /*String*/
             $error = "Unknown destination " . $this->destination . ". Cannot handle subscription request";
             if (LOGGING) {
                 Log::log(LoggingConstants::ERROR, $error);
             }
             return new ErrMessage($this->messageId, new Exception($error));
         }
         return new AckMessage($this->messageId, $clientId, null, $headers);
     } else {
         if ($this->operation == "1") {
             /*String*/
             $dsId = $this->headers["DSId"];
             /*Subscriber*/
             $subscriber = SubscriptionsManager::getInstance()->getSubscriber($dsId);
             if ($subscriber == null) {
                 return new ErrMessage($this->messageId, new Exception("Unable to unsubscribe - unknown client"));
             }
             /*IDestination*/
             $destination = $subscriber->getDestination();
             $destination->getServiceHandler()->handleUnsubscribe($subscriber);
             SubscriptionsManager::getInstance()->removeSubscriber($dsId);
         } else {
             if ($this->operation == "2") {
                 /*String*/
                 $dsId = $this->headers["DSId"];
                 /*Subscriber*/
                 $subscriber = SubscriptionsManager::getInstance()->getSubscriber($dsId);
                 if ($subscriber == null) {
                     /*String*/
                     $error = "Invalid client id " . $dsId;
                     if (LOGGING) {
                         Log::log(LoggingConstants::ERROR, $error);
                     }
                     return new ErrMessage($this->messageId, new Exception($error));
                 }
                 /*IDestination*/
                 $destination = $subscriber->getDestination();
                 //Log::log( LoggingConstants::INFO, "Getting messages from " . $destination->getServiceHandler() );
                 /*ArrayList*/
                 $messages = $destination->getServiceHandler()->getMessages($subscriber);
                 $subscriber->setLastRequestTime(microtime(true));
                 if (count($messages) == 0) {
                     return new AckMessage(null, null, null, array());
                 }
                 return $this->createCmdMessage("4", $messages);
             } else {
                 if ($this->operation == "5") {
                     /*Hashtable*/
                     $headers = array();
                     $guid = new GUID();
                     $headers["DSId"] = $guid->toString();
                     return new AckMessage($this->messageId, $this->clientId, null, $headers);
                 } else {
                     if ($this->operation == "9") {
                         ThreadContext::setCallerCredentials(null);
                     } else {
                         if ($this->operation == "8") {
                             $arr = $this->body->getBody();
                             $adaptingType = $arr[0];
                             $authData = split(":", base64_decode($adaptingType->defaultAdapt()));
                             $credentials = new Credentials($authData[0], $authData[1]);
                             $authHandler = ORBSecurity::getAuthenticationHandler(ThreadContext::getORBConfig());
                             if (LOGGING) {
                                 Log::log(LoggingConstants::DEBUG, "got auth handler " . get_class($authHandler));
                             }
                             if ($authHandler == null) {
                                 $errorMessage = new ErrMessage($this->messageId, new ServiceException("Missing authentication handler"));
                                 $errorMessage->faultCode = "Client.Authentication";
                                 return $errorMessage;
                             }
                             try {
                                 $authHandler->checkCredentials($credentials->getUserId(), $credentials->getPassword(), $request);
                                 if (LOGGING) {
                                     Log::log(LoggingConstants::DEBUG, "credentials are valid ");
                                 }
                                 ThreadContext::setCallerCredentials($credentials);
                             } catch (Exception $e) {
                                 if (LOGGING) {
                                     Log::log(LoggingConstants::EXCEPTION, "authentication exception" . $e);
                                 }
                                 $errorMessage = new ErrMessage($this->messageId, $e);
                                 $errorMessage->faultCode = "Client.Authentication";
                                 return $errorMessage;
                             }
                             return new AckMessage($this->messageId, $this->clientId, null);
                         }
                     }
                 }
             }
         }
     }
     //echo $this->operation; exit;
     return new AckMessage($this->messageId, $this->clientId, $returnValue, array());
 }