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diff --git a/TAO/docs/tutorials/Quoter/RTCORBA/docs/distributor.html b/TAO/docs/tutorials/Quoter/RTCORBA/docs/distributor.html new file mode 100644 index 00000000000..8738fbe78a0 --- /dev/null +++ b/TAO/docs/tutorials/Quoter/RTCORBA/docs/distributor.html @@ -0,0 +1,302 @@ +<!-- $Id$ --> + +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> +<head> + <title>Stock Distributor implementation for the Stock Quoter Publisher/Subscriber Real-time CORBA Service</title> +</head> + +<body + text = "#000000" + link = "#000fff" + vLink= "#ff0f0f" + aLink = "#0000ff" + bgColor = "#ffffff"> + +<hr><h2>Stock Distributor implementation for the Stock Quoter Publisher/Subscriber Real-time CORBA Service</h2><hr> + +<h3>Implementation of StockQuoter interface</h3> + +This interface is used by brokers to get detailed stock information. <P> + +The Stock_StockQuoter_i class is generated automatically by the IDL compiler (using the -GI flag), +which is a subclass of POA_Stock::StockQuoter class. <P> + +<h4>Implementing the get_stock_info () member function</h4> + +<li>Call the get_stock_info () function of Stock_Database instance.</li> + +<PRE> + Stock::StockInfo *stock = STOCK_DATABASE->get_stock_info (stock_name); +</PRE> + +<hr><h3>Implementation of StockDistributorHome interface</h3> + +This interface is used to register the necessary factories and mappings with the specified orb and +create StockDistributor objects. <P> + +The Stock_StockDistributorHome_i class is generated automatically by the IDL compiler (using the -GI flag), +which is a subclass of POA_Stock::StockDistributorHome class. <P> + +This class is also a subclass of ACE_Event_Handler, which can be used as an event handler. <P> + +<h4>Implementing the Constructor</h4> + +The main steps of this function are described as follows: <P> + +<li>Register this class as an event handler with the ORB to catch ctrl-c from the command line. </li> + +<PRE> + if (orb_->orb_core ()->reactor ()->register_handler (SIGINT, this) == -1) + ACE_DEBUG ((LM_DEBUG, "ERROR: Failed to register as a signal handler: %p\n", + "register_handler\n")); +</PRE> + +<li>Register the necessary factories and mappings with the specified orb.</li> + +<PRE> + Stock::StockName_init *stockname_factory = new Stock::StockName_init; + orb->register_value_factory (stockname_factory->tao_repository_id (), + stockname_factory + ACE_ENV_ARG_PARAMETER); + + Stock::Cookie_init *cookie_factory = new Stock::Cookie_init; + orb->register_value_factory (cookie_factory->tao_repository_id (), + cookie_factory + ACE_ENV_ARG_PARAMETER); + + Stock_PriorityMapping::register_mapping (orb); +</PRE> + +<li>Initialize the Stock database.</li> + +<PRE> + STOCK_DATABASE->activate (THR_NEW_LWP | THR_JOINABLE, 1); +</PRE> + +<li>Create a CORBA::PolicyList for the child POA.</li> + +This step include several sub-stpes: +<OL> +<li> Get a reference to the RTORB.</li> +<li> Initialize a CORBA::PolicyList object.</li> +<li> Create a SERVER_DECLARED priority model policy and add it into the former CORBA::PolicyList object.</li> +<li> Create a threadpool with lanes for the distributor. Since the brokers have various priorities, +create a lane for each priority.</li> +<li> Create a thread pool policy using the former threadpool and add it into the former CORBA::PolicyList object.</li> +<li> Create a child POA using the former CORBA::PolicyList and narrow it to RTPOA.</li> +</OL> + +<PRE> + CORBA::Object_var obj = orb_->resolve_initial_references ("RTORB"); + RTCORBA::RTORB_var rt_orb = RTCORBA::RTORB::_narrow (obj.in ()); + + TAO::Utils::PolicyList_Destroyer policies (2); + policies.length (2); + + policies[0] = + rt_orb->create_priority_model_policy (RTCORBA::SERVER_DECLARED, + Stock::Priority_Mapping::VERY_LOW); + + RTCORBA::ThreadpoolLanes lanes (5); lanes.length (5); + + for (CORBA::ULong i = 0; i < lanes.length (); ++i) + { + lanes[i].lane_priority = static_cast<RTCORBA::Priority> (i); + lanes[i].static_threads = 5; + lanes[i].dynamic_threads = 0; + } + + RTCORBA::ThreadpoolId threadpool_id = + rt_orb->create_threadpool_with_lanes (1024*1024, + lanes, + false, false, 0, 0); + + policies[1] = rt_orb->create_threadpool_policy (threadpool_id); + + PortableServer::POA_var poa = this->_default_POA (); + PortableServer::POAManager_var poa_mgr = poa->the_POAManager (); + + PortableServer::POA_var child_poa = + poa->create_POA ("StockDistributor_POA", + poa_mgr.in (), + policies); + + this->rt_poa_ = RTPortableServer::POA::_narrow (child_poa.in ()); +</PRE> + +<li>Create the initial distributor reference. </li> + +<PRE> + this->create_distributor (); +</PRE> + +<h4>Implementing the create_distributor () member function</h4> + +<li>Create a new instance of the StockDistributor_i. Then activate it under the located POA. +This will cause the object to have the CLIENT_PROPAGATED policies. </li> + +<PRE> + StockDistributor_i *servant = new StockDistributor_i (this->rt_poa_.in ()); + PortableServer::ServantBase_var distributor_owner_transfer = servant; + this->dist_id_ = this->rt_poa_->activate_object (servant); +</PRE> + +<h4>Implementing the create () member function</h4> + +<li>Get and narrow the StockDistributor object reference and return it. </li> + +<PRE> + obj = this->rt_poa_->id_to_reference (this->dist_id_.in ()); + return Stock::StockDistributor::_narrow (obj.in ()); +</PRE> + +<h4>Implementing the handle_signal () member function</h4> + +<li>Get and shutdown the distributor object and the orb used by it. </li> + +<PRE> + CORBA::Object_var obj (this->rt_poa_->id_to_reference (this->dist_id_.in ())); + Stock::StockDistributor_var dist (Stock::StockDistributor::_narrow (obj.in ())); + dist->shutdown (); + + this->orb_->shutdown (true); +</PRE> + +<hr><h3>Implementation of StockDistributor interface</h3> + +This interface is used for Stock Distributor server. <P> +The Stock_StockDistributor_i class is generated automatically by the IDL compiler (using the -GI flag), +which is a subclass of POA_Stock::StockDistributor class. <P> + +<h4>Implementing the Constructor</h4> + +<PRE> + StockDistributor_i::StockDistributor_i (RTPortableServer::POA_ptr poa) + : rate_ (3), // Default is 3 seconds (3000 milliseconds). + active_ (false), + rt_poa_ (RTPortableServer::POA::_duplicate (poa)), + orb_ (CORBA::ORB::_duplicate (poa->_get_orb ())) +</PRE> + +The "rate_" and "active_" are two private members of the Stock_StockDistributor_i class. They stand +for the notification rate and the active state of the StockDistributor object. <P> + +<h4>Implementing the subscribe_notifier () member function</h4> + +The main steps of this function are described as follows: <P> + +<li>Get the write thread mutex of the subscriber map.</li> <P> + +<li>Generate an unique id for the cookie and use it to create a new Cookie object.</li> <P> + +<li>Insert the StockNameConsumer object and its priority into the StockDistributor object's subscriber map, +using the cookie id as the key.</li> <P> + +<li>Return the Cookie object.</li> <P> + +<h4>Implementing the unsubscribe_notifier () member function</h4> + +The main steps of this function are described as follows: <P> + +<li>Check the value of the Cookie object.</li> <P> + +<li>Get the write thread mutex of the subscriber map.</li> <P> + +<li>Search for the Cookie object in the argument in the StockDistributor object's subscriber map.</li> <P> + +<li>Erase the Cookie object from the StockDistributor object's subscribers' map.</li> <P> + +<li>Return the StockNameConsumer object which is related to the erased Cookie object.</li> <P> + +<h4>Implementing the provide_quoter_info () member function</h4> + +<li>Get the read thread mutex of the subscriber map.</li> <P> + +<li>Search for the Cookie object in the argument in the StockDistributor object's subscriber map.</li> <P> + +<PRE> + CookieMap::const_iterator iter = this->subscribers_list_.find (ck->cookie_id ()); +</PRE> + +<li>Create a new instance of the StockQuoter object and activate it under the former RTPOA with the given priority.</li> <P> + +<PRE> + Stock_StockQuoter_i *quoter = new Stock_StockQuoter_i; + PortableServer::ServantBase_var owner_transfer (quoter); + + PortableServer::ObjectId *oid = + this->rt_poa_->activate_object_with_priority (quoter, + iter->second.second); + + CORBA::Object_var obj = rt_poa_->id_to_reference (*oid); + Stock::StockQuoter_var quoter_var = ::Stock::StockQuoter::_narrow (obj.in ()); +</PRE> + +<li>Return the StockQuoter object reference.</li> <P> + +<h4>Implementing the start () member function</h4> + +Set the active state of the StockDistributor object to true and create a thread to publish the stock information +to the Stock Broker clients. <P> + +The main steps of this thread function are described as follows: <P> +While the state of the StockDistributor object is active, continue the following looping: + +<li>Get the read thread mutex of the subscriber map.</li> + +<li>Publish the stock information to all the StockNameConsumer objects that have subscribed.</li> +<PRE> + for (Stock_StockDistributor_i::CookieMap::iterator iter = this->subscribers_list_.begin (); + iter != this->subscribers_list_.end (); + ++iter) + { + try + { + // Set the designated priority for current request. + CORBA::Object_var obj = orb_->resolve_initial_references ("RTCurrent"); + RTCORBA::Current_var rt_current = + RTCORBA::Current::_narrow (obj); + + rt_current->the_priority (iter->second.second); + + // Tell the database to push its information to the + // <consumer>, which passes along the CORBA priority + // in the service_context list of the GIOP message. + STOCK_DATABASE->publish_stock_info (iter->second.first); + } + catch (CORBA::Exception &ex) + { + ACE_PRINT_EXCEPTION (ex, "Stock_StockDistributor_i::svc: "); + } + } +</PRE> + +<li>Sleep for the specified amount of seconds given in the notification rate.</li> + +<h4>Implementing the stop () member function</h4> + +<li>Set the active state of StockDistributor object to false.</li> + +<h4>Implementing the shutdown () member function</h4> + +<li>Stop publishing events.</li> + +<PRE> + this->stop (); +</PRE> + +<li>Deactivate the StockDistributor object.</li> + +<PRE> + ::Stock::StockDistributor_var dist = this->_this (); + PortableServer::ObjectId_var oid = this->rt_poa_->reference_to_id (dist.in ()); + + this->rt_poa_->deactivate_object (oid.in ()); +</PRE> + +<hr><b>Email: </b><a href="mailto:"</a<ADDRESS>shanshan.jiang@vanderbilt.edu</ADDRESS> + +</body> + +</html> |