TAO/tao/Service_Callbacks.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    Service_Callbacks.h
   6  *
   7  * This is a generic interface that would be used to override many
   8  * of the default functionalities that the ORB provides by the
   9  * services if they have been loaded in to the ORB_Core
  10  *
  11  *  @author Bala Natarajan <bala@cs.wustl.edu>
  12  */
  13 //=============================================================================
  14
  15 #ifndef TAO_SERVICE_CALLBACK_H
  16 #define TAO_SERVICE_CALLBACK_H
  17
  18 #include /**/ "ace/pre.h"
  19
  20 #include "tao/Basic_Types.h"
  21
  22 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  23 # pragma once
  24 #endif /* ACE_LACKS_PRAGMA_ONCE */
  25
  26 #include /**/ "tao/TAO_Export.h"
  27 #include "tao/Invocation_Utils.h"
  28 #include "tao/Object.h"
  29 #include "tao/Service_Context.h"
  30
  31 TAO_BEGIN_VERSIONED_NAMESPACE_DECL
  32
  33 class TAO_Profile;
  34 class TAO_MProfile;
  35 class TAO_Stub;
  36
  37 namespace CORBA
  38 {
  39   class Object;
  40   typedef Object *Object_ptr;
  41 }
  42
  43 namespace IOP
  44 {
  45   class ServiceContextList;
  46 }
  47
  48 /**
  49  * @class TAO_Service_Callbacks
  50  *
  51  * @brief An Abstract Base class for the hooks in the ORB.
  52  *
  53  * This class (would) define all the hooks that may be needed by
  54  * the ORB to override some of its default behavior. The methods
  55  * can be potentially used to call service level specific
  56  * processing that may be required.
  57  */
  58 class TAO_Export TAO_Service_Callbacks
  59 {
  60 public:
  61   enum Profile_Equivalence
  62   {
  63     EQUIVALENT,
  64     NOT_EQUIVALENT,
  65     DONT_KNOW
  66   };
  67
  68   /// Dtor
  69   virtual ~TAO_Service_Callbacks ();
  70
  71   /// Select the profile from MProfile as the needs of the services
  72   /// may be. Return the profile in @a pfile
  73   virtual CORBA::Boolean select_profile (const TAO_MProfile &mprofile,
  74                                          TAO_Profile *&pfile);
  75
  76   /// Check whether @a obj is nil or not.
  77   virtual CORBA::Boolean object_is_nil (CORBA::Object_ptr obj);
  78
  79   /// Check for equivalency of the two profiles
  80   virtual Profile_Equivalence is_profile_equivalent (const TAO_Profile *,
  81                                                      const TAO_Profile *);
  82
  83   /// Calculate the hash value..
  84   virtual CORBA::ULong hash_ft (TAO_Profile *p,
  85                                 CORBA::ULong m);
  86
  87   /// Verify if condition is given for LOCATION_FORWARD_PERM reply
  88   virtual CORBA::Boolean is_permanent_forward_condition (const CORBA::Object_ptr obj,
  89                                                          const TAO_Service_Context &service_context) const;
  90
  91   /// Allow the service layer to decide whether the COMM_FAILURE
  92   /// exception should be thrown or a reinvocation is needed
  93   virtual TAO::Invocation_Status raise_comm_failure (
  94       IOP::ServiceContextList &clist,
  95       TAO_Profile *profile);
  96
  97   /// Allow the service layer to decide whether the TRANSIENT
  98   /// exception should be thrown or a reinvocation is needed
  99   virtual TAO::Invocation_Status raise_transient_failure (
 100       IOP::ServiceContextList &clist,
 101       TAO_Profile *profile);
 102 };
 103
 104 TAO_END_VERSIONED_NAMESPACE_DECL
 105
 106 #include /**/ "ace/post.h"
 107
 108 #endif /*TAO_SERVICE_CALLBACK_H*/