TAO/tests/POA/On_Demand_Loading/Servant_Activator.h

   1 //=============================================================================
   2 /**
   3  *  @file     Servant_Activator.h
   4  *
   5  *   Defines a <ServantActivator_i> class, which uses a
   6  *   Servant_Manager to activate a servant by loading it and
   7  *   associates it with an object on-demand.
   8  *
   9  *  @author  Kirthika Parameswaran <kirthika@cs.wustl.edu>
  10  */
  11 //=============================================================================
  12
  13 #ifndef SERVANT_ACTIVATOR_H
  14 #define SERVANT_ACTIVATOR_H
  15
  16 #include "Servant_Manager.h"
  17 #include "tao/PortableServer/ServantActivatorC.h"
  18 #include "tao/LocalObject.h"
  19
  20 /**
  21  * Servant Activator for the test servant.
  22  *
  23  * This class associates an unassociated servant with an object in
  24  * the POA Active Object Map.
  25  */
  26 class ServantActivator_i :
  27   public virtual PortableServer::ServantActivator,
  28   public virtual ::CORBA::LocalObject
  29
  30 {
  31 public:
  32   /// Initialization.
  33   ServantActivator_i (CORBA::ORB_ptr orb);
  34
  35   /**
  36    * This method is invoked by a POA with USE_SERVANT_MANAGER and
  37    * RETAIN policies, whenever it receives a request for a test object
  38    * that is not currently active. When an servant pointer
  39    * corresponding to objectId is not found in the Active Object Map,
  40    * the POA hands over the job of obtaining the servant to the
  41    * Servant Manager. Depending upon whether the POA is created with
  42    * RETAIN or NON_RETAIN as the servant_retention policy, the Servant
  43    * Activator or the Servant Locator interface is invoked
  44    * respectively.
  45    */
  46   virtual PortableServer::Servant incarnate (const PortableServer::ObjectId &oid,
  47                                              PortableServer::POA_ptr poa);
  48
  49   /**
  50    * This method is invoked whenever a test servant is
  51    * deactivated. This occurs when the POA is destroyed or the Object
  52    * is deactivated. When the POA is getting destroyed, it needs to
  53    * deactivate every object in the Active Object Map and on that call
  54    * the ServantActivator invokes this method which will destroy the
  55    * servant associated with the object.
  56    */
  57   virtual void etherealize (const PortableServer::ObjectId &oid,
  58                             PortableServer::POA_ptr adapter,
  59                             PortableServer::Servant servant,
  60                             CORBA::Boolean cleanup_in_progress,
  61                             CORBA::Boolean remaining_activations);
  62
  63   /// Returns an ObjectId when given a DLL name and the factory
  64   /// function in the DLL that will create an appropriate Servant.
  65   PortableServer::ObjectId_var create_dll_object_id (const char *dllname,
  66                                                      const char *factory_function);
  67
  68 private:
  69   /**
  70    * An ServantManager object that provides utility methods.  The
  71    * methods include obtaining the servant using an ACE_DLL object,
  72    * destroying the servant and extracting the dllname and factory
  73    * function from the ObjectId.
  74    */
  75   ServantManager_i servant_manager_;
  76 };
  77
  78 #endif /* SERVANT_ACTIVATOR_H */