TAO_Singleton< TYPE, ACE_LOCK > Class Template Reference

TAO-specific Singleton class. More...

#include <TAO_Singleton.h>

Inheritance diagram for TAO_Singleton< TYPE, ACE_LOCK >:

Collaboration diagram for TAO_Singleton< TYPE, ACE_LOCK >:

List of all members.

Public Member Functions
virtual void	cleanup (void *param=0)
Static Public Member Functions
static TYPE *	instance (void)
	Global access point to the Singleton.
static void	dump (void)
	Dump the state of the object.
Protected Member Functions
	TAO_Singleton (void)
	Default constructor.
Static Protected Member Functions
static TAO_Singleton< TYPE, ACE_LOCK > *&	instance_i (void)
	Get pointer to the TAO Singleton instance.
Protected Attributes
TYPE	instance_
	Contained instance.
Static Protected Attributes
static TAO_Singleton< TYPE, ACE_LOCK > *	singleton_ = 0
	Pointer to the Singleton (ACE_Cleanup) instance.

---

Detailed Description

template<class TYPE, class ACE_LOCK>
class TAO_Singleton< TYPE, ACE_LOCK >

TAO-specific Singleton class.

TAO_Singletons are used by TAO to register TAO-specific singleton instances with the TAO_Object_Manager. This ensures that TAO singletons are isolated from ACE's Object_Manager, thus allowing TAO to be safely dynamically unloaded.

Definition at line 47 of file TAO_Singleton.h.

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Constructor & Destructor Documentation

template<class TYPE , class ACE_LOCK >

TAO_Singleton< TYPE, ACE_LOCK >::TAO_Singleton

(

void

)

[protected]

Default constructor.

Definition at line 14 of file TAO_Singleton.inl.

{
}

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Member Function Documentation

template<class TYPE , class ACE_LOCK >

void TAO_Singleton< TYPE, ACE_LOCK >::cleanup

(

void *

param = 0

)

[virtual]

Cleanup method, used by ace_cleanup_destroyer to destroy the singleton.

Reimplemented from ACE_Cleanup.

Definition at line 108 of file TAO_Singleton.cpp.

{
  delete this;
  TAO_Singleton<TYPE, ACE_LOCK>::instance_i () = 0;
}

template<class TYPE , class ACE_LOCK >

void TAO_Singleton< TYPE, ACE_LOCK >::dump

(

void

)

[static]

Dump the state of the object.

Definition at line 28 of file TAO_Singleton.cpp.

{
#if defined (ACE_HAS_DUMP)
  ACE_TRACE ("TAO_Singleton<TYPE, ACE_LOCK>::dump");

#if !defined (ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES)
  ACE_DEBUG ((LM_DEBUG,  ACE_TEXT ("instance_ = %x"),
              TAO_Singleton<TYPE, ACE_LOCK>::instance_i ()));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
#endif /* ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES */
#endif /* ACE_HAS_DUMP */
}

template<class TYPE , class ACE_LOCK >

TYPE * TAO_Singleton< TYPE, ACE_LOCK >::instance

(

void

)

[static]

Global access point to the Singleton.

Definition at line 56 of file TAO_Singleton.cpp.

{
  ACE_TRACE ("TAO_Singleton<TYPE, ACE_LOCK>::instance");

  TAO_Singleton<TYPE, ACE_LOCK> *&singleton =
    TAO_Singleton<TYPE, ACE_LOCK>::instance_i ();

  // Perform the Double-Check pattern...
  if (singleton == 0)
    {
      if (TAO_Singleton_Manager::starting_up () ||
          TAO_Singleton_Manager::shutting_down ())
        {
          // The program is still starting up, and therefore assumed
          // to be single threaded.  There's no need to double-check.
          // Or, the TAO_Singleton_Manager instance has been destroyed,
          // so the preallocated lock is not available.  Either way,
          // don't register for destruction with the
          // TAO_Singleton_Manager:  we'll have to leak this instance.

          ACE_NEW_RETURN (singleton, (TAO_Singleton<TYPE, ACE_LOCK>), 0);
        }
      else
        {
#if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0)
          // Obtain a lock from the ACE_Object_Manager.  The pointer
          // is static, so we only obtain one per TAO_Singleton
          // instantiation.
          static ACE_LOCK *lock = 0;
          if (ACE_Object_Manager::get_singleton_lock (lock) != 0)
            // Failed to acquire the lock!
            return 0;

          ACE_GUARD_RETURN (ACE_LOCK, ace_mon, *lock, 0);

          if (singleton == 0)
            {
#endif /* ACE_MT_SAFE */
              ACE_NEW_RETURN (singleton, (TAO_Singleton<TYPE, ACE_LOCK>), 0);

              // Register for destruction with TAO_Singleton_Manager.
              TAO_Singleton_Manager::at_exit (singleton, 0, typeid (TYPE).name());
#if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0)
            }
#endif /* ACE_MT_SAFE */
        }
    }

  return &singleton->instance_;
}

template<class TYPE , class ACE_LOCK >

TAO_Singleton< TYPE, ACE_LOCK > *& TAO_Singleton< TYPE, ACE_LOCK >::instance_i

(

void

)

[static, protected]

Get pointer to the TAO Singleton instance.

Definition at line 42 of file TAO_Singleton.cpp.

{
#if defined (ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES)
  // Pointer to the Singleton instance.  This works around a bug with
  // G++ and it's (mis-)handling of templates and statics...
  static TAO_Singleton<TYPE, ACE_LOCK> *singleton_ = 0;

  return singleton_;
#else
  return TAO_Singleton<TYPE, ACE_LOCK>::singleton_;
#endif /* ACE_LACKS_STATIC_DATA_MEMBER_TEMPLATES */
}

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Member Data Documentation

template<class TYPE, class ACE_LOCK>

TYPE TAO_Singleton< TYPE, ACE_LOCK >::instance_ [protected]

Contained instance.

Definition at line 66 of file TAO_Singleton.h.

template<class TYPE, class ACE_LOCK>

TAO_Singleton< TYPE, ACE_LOCK > * TAO_Singleton< TYPE, ACE_LOCK >::singleton_ = 0 [static, protected]

Pointer to the Singleton (ACE_Cleanup) instance.

Definition at line 70 of file TAO_Singleton.h.

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

• TAO_Singleton.h
• TAO_Singleton.cpp
• TAO_Singleton.inl