OmniEvents

OmniEvents::EventChannel_i Class Reference

Servant for CosEventChannelAdmin::EventChannel objects, also inherits from omni_thread. More...

#include <EventChannel.h>

Inheritance diagram for OmniEvents::EventChannel_i:
Collaboration diagram for OmniEvents::EventChannel_i:

List of all members.

Public Member Functions

CosEventChannelAdmin::ConsumerAdmin_ptr for_consumers ()
CosEventChannelAdmin::SupplierAdmin_ptr for_suppliers ()
void destroy ()
CORBA::Boolean is_alive ()
 'ping' method inherited from FT::PullMonitorable.
 EventChannel_i (EventChannelStore *store=NULL)
 ~EventChannel_i ()
 Cleans up the _poa, if this object is deleted before its thread starts.
void activate (const char *channelName, const PersistNode *node=NULL)
 Creates the channel's POA, and any child objects.
void start ()
 Warn about interface change.
void * run_undetached (void *)
 Entry point for the channel's thread.
void mainLoop ()
 The main loop for a channel.
void _add_ref ()
void _remove_ref ()
 Shutdown the thread when refCount reaches zero.
void output (ostream &os)
ConsumerAdmin_iconsumerAdmin () const
const PersistNodeproperties () const
CORBA::ULong pullRetryPeriod_ms () const
CORBA::ULong maxQueueLength () const
CORBA::ULong maxNumProxies () const
unsigned long cyclePeriod_ns () const

Private Member Functions

void setInsName (const string v)
 Construct a new Mapper object, and registers it in the INSPOA.
void createPoa (const char *channelName)
 Constructs the main POA for this channel.

Private Attributes

EventChannelStore_eventChannelStore
SupplierAdmin_i_supplierAdmin
ConsumerAdmin_i_consumerAdmin
PortableServer::POAManager_var _poaManager
bool _shutdownRequested
PersistNode _properties
Mapper_mapper
omni_mutex _lock
int _refCount

Detailed Description

Servant for CosEventChannelAdmin::EventChannel objects, also inherits from omni_thread.

Each EventChannel contains five POAs, one for each of the proxy types, and one for the XXXAdmins and EventChannel itself. This POA also contains the ProxyManager objects that are used to manage three of the four proxy object types.

Here's a summary of the POAs, and their contents:

     +-POA: EventChannel-----------------------------------------------+
     |                                                                 |
     |                      Obj: EventChannel_i                        |
     |                                                                 |
     |       Obj: SupplierAdmin_i           Obj: ConsumerAdmin_i       |
     |                                                                 |
     |                                 Obj: ProxyPushSupplierManager   |
     |                                                                 |
     |   +-POA: ProxyPushConsumer---+   +-POA: ProxyPushSupplier---+   |
     |   |                          |   |                          |   |
     |   | Obj: ProxyPushConsumer_i |   | Obj: ProxyPushSupplier_i |   |
     |   | (DEFAULT SERVANT)        |   | Obj: ProxyPushSupplier_i |   |
     |   |                          |   | Obj: ProxyPushSupplier_i |   |
     |   |                          |   | .                        |   |
     |   |                          |   | .                        |   |
     |   |                          |   | .                        |   |
     |   |                          |   |                          |   |
     |   +--------------------------+   +--------------------------+   |
     |                                                                 |
     |  Obj: ProxyPullConsumerManager  Obj: ProxyPullSupplierManager   |
     |                                                                 |
     |   +-POA: ProxyPullConsumer---+   +-POA: ProxyPullSupplier---+   |
     |   |                          |   |                          |   |
     |   | Obj: ProxyPullConsumer_i |   | Obj: ProxyPullSupplier_i |   |
     |   | Obj: ProxyPullConsumer_i |   | Obj: ProxyPullSupplier_i |   |
     |   | Obj: ProxyPullConsumer_i |   | Obj: ProxyPullSupplier_i |   |
     |   | .                        |   | .                        |   |
     |   | .                        |   | .                        |   |
     |   | .                        |   | .                        |   |
     |   |                          |   |                          |   |
     |   +--------------------------+   +--------------------------+   |
     |                                                                 |
     +-----------------------------------------------------------------+
 

All five POAs are single threaded, and managed by the same POAmanager. This enables the top level event loop (EventChannel::run()) to hold all incoming calls while it passes events from the ProxyConsumers over to the ProxySuppliers. This single threaded model simplifies[*] the implementation and avoids all of the locking overheads of a multi-threaded solution.

[*] That's the theory anyway... Actually the single threaded model complicates the underlying implementation, because omniORB treats single threaded POAs as a special case on top of multi-threaded ones, rather than the other way round! Ironic!

Definition at line 111 of file EventChannel.h.


Constructor & Destructor Documentation

OmniEvents::EventChannel_i::EventChannel_i ( EventChannelStore store = NULL)

Definition at line 71 of file EventChannel.cc.

OmniEvents::EventChannel_i::~EventChannel_i ( )

Cleans up the _poa, if this object is deleted before its thread starts.

Definition at line 129 of file EventChannel.cc.


Member Function Documentation

void OmniEvents::EventChannel_i::_add_ref ( )

Definition at line 250 of file EventChannel.cc.

void OmniEvents::EventChannel_i::_remove_ref ( )

Shutdown the thread when refCount reaches zero.

Definition at line 260 of file EventChannel.cc.

References _lock, and _refCount.

Referenced by activate().

void OmniEvents::EventChannel_i::activate ( const char *  channelName,
const PersistNode node = NULL 
)
ConsumerAdmin_i& OmniEvents::EventChannel_i::consumerAdmin ( ) const [inline]

Definition at line 168 of file EventChannel.h.

Referenced by OmniEvents::SupplierAdmin_i::SupplierAdmin_i().

void OmniEvents::EventChannel_i::createPoa ( const char *  channelName) [private]

Constructs the main POA for this channel.

Policies are: PERSISTENT, USER_ID, SINGLE_THREAD_MODEL. POA name is set to channelName.

Definition at line 324 of file EventChannel.cc.

References OmniEvents::Servant::_poa, _poaManager, and DB.

Referenced by activate().

unsigned long OmniEvents::EventChannel_i::cyclePeriod_ns ( ) const [inline]

Definition at line 181 of file EventChannel.h.

References CYCLE_PERIOD_NS.

Referenced by OmniEvents::SupplierAdmin_i::SupplierAdmin_i().

void OmniEvents::EventChannel_i::destroy ( )

Definition at line 53 of file EventChannel.cc.

build buildd omnievents src EventChannel cc build buildd omnievents src EventChannel cc CosEventChannelAdmin::ConsumerAdmin_ptr OmniEvents::EventChannel_i::for_consumers ( )

Definition at line 37 of file EventChannel.cc.

CosEventChannelAdmin::SupplierAdmin_ptr OmniEvents::EventChannel_i::for_suppliers ( )

Definition at line 45 of file EventChannel.cc.

CORBA::Boolean OmniEvents::EventChannel_i::is_alive ( ) [inline]

'ping' method inherited from FT::PullMonitorable.

Definition at line 121 of file EventChannel.h.

void OmniEvents::EventChannel_i::mainLoop ( )

The main loop for a channel.

Work is strictly separated into two phases. Most of the time, all of the POAs are active, and receiving incoming calls. Periodically, incoming calls are held and the channel collects new events from the consumers and sends them to the suppliers.

Incoming call handlers are all designed to complete in the absolute minimum time. This enables the POAs to be single threaded, and to hold incoming calls without having to wait a long time for ongoing invokations to complete. Sadly, it's not possible to implement ProxyPullSupplier::pull() 'properly' without blocking, so our version just raises TRANSIENT if there is no event immediately available.

Outgoing calls are always sent as deferred requests, to avoid blocking while we wait for them to return.

Definition at line 223 of file EventChannel.cc.

CORBA::ULong OmniEvents::EventChannel_i::maxNumProxies ( ) const [inline]

Definition at line 179 of file EventChannel.h.

References MAX_NUM_PROXIES.

Referenced by OmniEvents::ProxyPullSupplierManager::incarnate().

CORBA::ULong OmniEvents::EventChannel_i::maxQueueLength ( ) const [inline]

Definition at line 177 of file EventChannel.h.

References MAX_QUEUE_LENGTH.

void OmniEvents::EventChannel_i::output ( ostream &  os)

Definition at line 283 of file EventChannel.cc.

const PersistNode& OmniEvents::EventChannel_i::properties ( ) const [inline]

Definition at line 170 of file EventChannel.h.

CORBA::ULong OmniEvents::EventChannel_i::pullRetryPeriod_ms ( ) const [inline]
void * OmniEvents::EventChannel_i::run_undetached ( void *  )

Entry point for the channel's thread.

Calls mainLoop() and waits for it to exit. Handles any exceptions, and shuts down the channel once the main loop has finished.

Definition at line 155 of file EventChannel.cc.

void OmniEvents::EventChannel_i::setInsName ( const string  v) [private]

Construct a new Mapper object, and registers it in the INSPOA.

Definition at line 295 of file EventChannel.cc.

References _mapper, and OmniEvents::Mapper::destroy().

Referenced by activate().

void OmniEvents::EventChannel_i::start ( ) [inline]

Warn about interface change.

Definition at line 135 of file EventChannel.h.

References DB.


Member Data Documentation

Definition at line 198 of file EventChannel.h.

Referenced by activate().

omni_mutex OmniEvents::EventChannel_i::_lock [private]

Definition at line 203 of file EventChannel.h.

Referenced by _remove_ref().

Definition at line 202 of file EventChannel.h.

Referenced by setInsName().

PortableServer::POAManager_var OmniEvents::EventChannel_i::_poaManager [private]

Definition at line 199 of file EventChannel.h.

Referenced by createPoa().

Definition at line 201 of file EventChannel.h.

Referenced by activate().

Definition at line 204 of file EventChannel.h.

Referenced by _remove_ref().

Definition at line 200 of file EventChannel.h.

Definition at line 197 of file EventChannel.h.

Referenced by activate().


The documentation for this class was generated from the following files: