TAO/tests/POA/Loader/Servant_Activator.h

   1 //=============================================================================
   2 /**
   3  *  @file     Servant_Activator.h
   4  *
   5  *   Defines a <ServantActivator> class, which activates a servant by
   6  *   obtaining it and associates it with an object on-demand.
   7  *
   8  *  @author  Kirthika Parameswaran <kirthika@cs.wustl.edu>
   9  */
  10 //=============================================================================
  11
  12 #ifndef SERVANT_ACTIVATOR_H
  13 #define SERVANT_ACTIVATOR_H
  14
  15 #include "tao/PortableServer/PortableServer.h"
  16 #include "tao/PortableServer/ServantActivatorC.h"
  17 #include "tao/LocalObject.h"
  18
  19 #include "tao/ORB.h"
  20
  21 #include "ace/DLL.h"
  22 #include "ace/Log_Msg.h"
  23
  24 /**
  25  * Servant Activator for the test servant.
  26  *
  27  * This class associates an unassociated servant with an object in
  28  * the POA Active Object Map.
  29  */
  30 class ServantActivator :
  31   public virtual PortableServer::ServantActivator,
  32   public virtual ::CORBA::LocalObject
  33 {
  34 public:
  35   /**
  36    * This typedef is used to typecast the void* obtained when finding
  37    * a symbol in the dll. Invoking the function pointer obtained would
  38    * get a servant.
  39    */
  40   typedef PortableServer::Servant
  41            (*SERVANT_FACTORY) (const PortableServer::ObjectId &oid,
  42                                PortableServer::POA_ptr poa,
  43                                CORBA::ORB_ptr orb);
  44
  45   /**
  46    * This typedef is used to obtain the garbage_collection_function symbol
  47    * in the dll. Invoking the function pointer obtained would then destroy
  48    * the servant.
  49    */
  50   typedef void
  51           (*SERVANT_GARBAGE_COLLECTOR) (const PortableServer::ObjectId &oid,
  52                                         PortableServer::POA_ptr,
  53                                         PortableServer::Servant servant);
  54
  55   /// Initialization.
  56   ServantActivator (CORBA::ORB_ptr orb,
  57                     const ACE_TCHAR *dllname,
  58                     const ACE_TCHAR *factory_function,
  59                     const ACE_TCHAR *garbage_collection_function);
  60
  61   /**
  62    * This method is invoked by a POA with USE_SERVANT_MANAGER and
  63    * RETAIN policies, whenever it receives a request for a
  64    * test object that is not currently active. When an servant
  65    * pointer corresponding to objectId is not found in the Active
  66    * Object Map, the POA hands over the job of obtaining the servant
  67    * to the Servant Manager. Depending upon whether the POA is created
  68    * with RETAIN or NON_RETAIN as the servant_retention policy, the
  69    * Servant Activator or the Servant Locator interface is invoked
  70    * respectively.
  71    */
  72   virtual PortableServer::Servant incarnate (const PortableServer::ObjectId &oid,
  73                                              PortableServer::POA_ptr poa);
  74
  75   /**
  76    * This method is invoked whenever a test object is
  77    * deactivated. This occurs when the POA is destroyed or the Object
  78    * is deactivated. When the POA is getting destroyed, it needs to
  79    * deactivate every object in the Active Object Map and on that call
  80    * the ServantActivator invokes this method which will destroy the
  81    * servant associated with the object.
  82    */
  83   virtual void etherealize (const PortableServer::ObjectId &oid,
  84                             PortableServer::POA_ptr adapter,
  85                             PortableServer::Servant servant,
  86                             CORBA::Boolean cleanup_in_progress,
  87                             CORBA::Boolean remaining_activations);
  88
  89 private:
  90   /// The ACE_DLL object which performs the task of loading the dll
  91   /// and accessing it.
  92   ACE_DLL dll_;
  93
  94   /// The function pointer of factory_function type.
  95   SERVANT_FACTORY servant_supplier_;
  96
  97   /// The function pointer of garbage_collection_function type.
  98   SERVANT_GARBAGE_COLLECTOR servant_garbage_collector_;
  99
 100   /// A reference to the ORB.
 101   CORBA::ORB_var orb_;
 102 };
 103
 104 #endif /* SERVANT_ACTIVATOR_H */