TAO_Intrusive_Ref_Count_Handle< T > Class Template Reference

Template class for smart-pointer to (intrusively) ref-counted object. More...

#include <Intrusive_Ref_Count_Handle_T.h>

Collaboration diagram for TAO_Intrusive_Ref_Count_Handle< T >:

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List of all members.

Public Member Functions

 TAO_Intrusive_Ref_Count_Handle ()
 Default Ctor - enters the "nil" state.
 TAO_Intrusive_Ref_Count_Handle (T *p, bool take_ownership=true)
 TAO_Intrusive_Ref_Count_Handle (const TAO_Intrusive_Ref_Count_Handle &b)
 Copy Ctor - claims a "copy" of rhs object's reference to T.
 ~TAO_Intrusive_Ref_Count_Handle ()
 Dtor.
TAO_Intrusive_Ref_Count_Handleoperator= (T *p)
TAO_Intrusive_Ref_Count_Handleoperator= (const TAO_Intrusive_Ref_Count_Handle &b)
T * operator-> () const
 Const Accessor to underlying pointer (T*) using arrow (->) operator.
bool is_nil () const
T * in () const
 Used to pass the underlying pointer as an "IN" argument to a method.
T *& inout ()
 Used to pass the underlying pointer as an "IN/OUT" argument to a method.
T *& out ()
 Used to pass the underlying pointer as an "OUT" argument to a method.
T * _retn ()

Private Member Functions

void claim ()
void drop ()

Private Attributes

T * ptr_

Detailed Description

template<typename T>
class TAO_Intrusive_Ref_Count_Handle< T >

Template class for smart-pointer to (intrusively) ref-counted object.

This class behaves just like a xxx_var type behaves. The only significant difference is that this class provides a "bool is_nil() const" method, and xxx_var types don't (they use the "bool CORBA::is_nil(xxx_ptr ptr)" method instead). For example,

typedef TAO_Intrusive_Ref_Count_Handle<PortableServer::ServantBase> MyServantBase_var;

The MyServantBase_var and the PortableServer::ServantBase_var are nearly idenitical. The only difference is that the MyServantBase_var has a "isNil()" method that indicates whether or not the smart pointer is in the 'nil' state or not.

This class can be used to "safely" deal with an instance of a servant. For example, we can use a single variable TAO_Intrusive_Ref_Count_Handle<Foo_i>

typedef TAO_Intrusive_Ref_Count_Handle<Foo_i> Foo_i_var; Foo_i_var servant_;

instead of using two variables

PortableServer::ServantBase_var servant_holder_; Foo_i* servant_;

to deal with the servant memory.

The Foo_i_var type does everything that the PortableServer::ServantBase_var type does. In addition, the Foo_i_var type can provide access to the servant as derived class via the arrow operator.


Constructor & Destructor Documentation

template<typename T>
ACE_INLINE TAO_Intrusive_Ref_Count_Handle< T >::TAO_Intrusive_Ref_Count_Handle  ) 
 

Default Ctor - enters the "nil" state.

template<typename T>
ACE_INLINE TAO_Intrusive_Ref_Count_Handle< T >::TAO_Intrusive_Ref_Count_Handle T *  p,
bool  take_ownership = true
 

Ctor - By default, takes ownership of passed-in "copy" of reference to T. But the second argument (bool) can be changed from the default value of 'true' to the non-default value of 'false'. The second argument dictates whether or not this handle object should take ownership of the passed-in pointer to the T object. By default, it takes ownership, leaving the reference counter of the T object unchanged. When it is instructed to not take ownership (false value for second arg), then the reference counter of the T object will be incremented so that this handle object has its own "copy".

template<typename T>
TAO_Intrusive_Ref_Count_Handle< T >::TAO_Intrusive_Ref_Count_Handle const TAO_Intrusive_Ref_Count_Handle< T > &  b  ) 
 

Copy Ctor - claims a "copy" of rhs object's reference to T.

template<typename T>
ACE_INLINE TAO_Intrusive_Ref_Count_Handle< T >::~TAO_Intrusive_Ref_Count_Handle  ) 
 

Dtor.


Member Function Documentation

template<typename T>
ACE_INLINE T * TAO_Intrusive_Ref_Count_Handle< T >::_retn  ) 
 

Used to take-away the underlying pointer from this smart pointer object. Caller becomes responsibe for the returned "copy" to the reference. Always leaves the smart pointer in the "nil" state upon return.

template<typename T>
ACE_INLINE void TAO_Intrusive_Ref_Count_Handle< T >::claim  )  [private]
 

Claim a "copy" of the reference-counted object by adding one to its reference counter. Do nothing if this smart pointer object is currently in the "nil" state.

template<typename T>
ACE_INLINE void TAO_Intrusive_Ref_Count_Handle< T >::drop  )  [private]
 

Drop our "copy" of the reference-counted object by removing one from its reference counter. Do nothing if this smart pointer object is currently in the "nil" state. Note that this method will always leave this smart pointer in the "nil" state upon its return.

template<typename T>
ACE_INLINE T * TAO_Intrusive_Ref_Count_Handle< T >::in  )  const
 

Used to pass the underlying pointer as an "IN" argument to a method.

template<typename T>
ACE_INLINE T *& TAO_Intrusive_Ref_Count_Handle< T >::inout  ) 
 

Used to pass the underlying pointer as an "IN/OUT" argument to a method.

template<typename T>
ACE_INLINE bool TAO_Intrusive_Ref_Count_Handle< T >::is_nil  )  const
 

Returns true if underlying pointer is NULL (0). Returns false otherwise.

template<typename T>
ACE_INLINE T * TAO_Intrusive_Ref_Count_Handle< T >::operator->  )  const
 

Const Accessor to underlying pointer (T*) using arrow (->) operator.

template<typename T>
TAO_Intrusive_Ref_Count_Handle& TAO_Intrusive_Ref_Count_Handle< T >::operator= const TAO_Intrusive_Ref_Count_Handle< T > &  b  ) 
 

Assignment Operator with const TAO_Smart_Ptr<T>& argument. Claims a "copy" of rhs object's reference to T.

template<typename T>
ACE_INLINE TAO_Intrusive_Ref_Count_Handle< T > & TAO_Intrusive_Ref_Count_Handle< T >::operator= T *  p  ) 
 

Assignment Operator with T* argument. Takes ownership of passed-in "copy" of reference to T.

template<typename T>
ACE_INLINE T *& TAO_Intrusive_Ref_Count_Handle< T >::out  ) 
 

Used to pass the underlying pointer as an "OUT" argument to a method.


Member Data Documentation

template<typename T>
T* TAO_Intrusive_Ref_Count_Handle< T >::ptr_ [private]
 

The underlying pointer to the (intrusively) reference-counted object. Set to 0 when this smart pointer is in the "nil" state. Otherwise, this smart pointer always owns a (reference-counted) "copy" of the object pointed to by the ptr_ data member.


The documentation for this class was generated from the following files:
Generated on Wed Nov 23 16:02:57 2005 for TAO by  doxygen 1.4.5