TGeoRCPtr< T > Class Template Reference

template<class T>
class TGeoRCPtr< T >

A reference counting-managed pointer for classes derived from TGeoExtension which can be used as C pointer.

Based on CodeProject implementation example

Example:

class MyExtension : public TGeoExtension {
public:
   MyExtension() : TGeoExtension(), fRC(0) {printf("Created MyExtension\n");}
   virtual ~MyExtension() {printf("Deleted MyExtension\n");}
 
   virtual TGeoExtension *Grab() const {fRC++; return (TGeoExtension*)this;}
   virtual void Release() const {assert(fRC > 0); fRC--; if (fRC ==0) delete this;}
   void print() const {printf("MyExtension object %p\n", this);}
private:
   mutable Int_t        fRC;           // Reference counter
   ClassDefOverride(MyExtension,1)
};

Usage:

// Module 1 creates an object
TGeoRCPtr<MyExtension> a2 = new MyExtension(); //fRC=1
 
// Module 2 grabs object
TGeoRCPtr<MyExtension> ptr2 = a2; //fRC=2
 
// Module 2 invokes a method
ptr2->Print();
(*ptr2).Print();
 
// Module 1 no longer needs object
 a2 = 0;      //RC=1
 
// Module 2 no longer needs object
 ptr2 = 0;    //object will be destroyed here

Note:

Event if one forgets to call ptr2 = 0, the object gets delete when the method using ptr2 gets out of scope.

Definition at line 65 of file TGeoRCPtr.h.

Public Member Functions
	TGeoRCPtr (const TGeoRCPtr &ptr)
	TGeoRCPtr (T *ptr=nullptr)
	~TGeoRCPtr ()
T *	Get () const
	operator bool () const
	operator T* () const
T &	operator* () const
T *	operator-> () const
TGeoRCPtr &	operator= (const TGeoRCPtr &ptr)
TGeoRCPtr &	operator= (T *ptr)
bool	operator== (const T *ptr)
bool	operator== (const TGeoRCPtr &ptr)

Private Attributes
T *	fPtr

#include <TGeoRCPtr.h>

Constructor & Destructor Documentation

TGeoRCPtr() [1/2]

template<class T >

TGeoRCPtr< T >::TGeoRCPtr ( T * ptr = nullptr )

inline

Definition at line 68 of file TGeoRCPtr.h.

TGeoRCPtr() [2/2]

template<class T >

TGeoRCPtr< T >::TGeoRCPtr ( const TGeoRCPtr< T > & ptr )

inline

Definition at line 75 of file TGeoRCPtr.h.

~TGeoRCPtr()

template<class T >

TGeoRCPtr< T >::~TGeoRCPtr ( )

inline

Definition at line 81 of file TGeoRCPtr.h.

Member Function Documentation

Get()

template<class T >

T * TGeoRCPtr< T >::Get ( ) const

inline

Definition at line 102 of file TGeoRCPtr.h.

operator bool()

template<class T >

TGeoRCPtr< T >::operator bool ( ) const

inline

Definition at line 109 of file TGeoRCPtr.h.

operator T*()

template<class T >

TGeoRCPtr< T >::operator T* ( ) const

inline

Definition at line 108 of file TGeoRCPtr.h.

operator*()

template<class T >

T & TGeoRCPtr< T >::operator* ( ) const

inline

Definition at line 107 of file TGeoRCPtr.h.

operator->()

template<class T >

T * TGeoRCPtr< T >::operator-> ( ) const

inline

Definition at line 106 of file TGeoRCPtr.h.

operator=() [1/2]

template<class T >

TGeoRCPtr & TGeoRCPtr< T >::operator= ( const TGeoRCPtr< T > & ptr )

inline

Definition at line 99 of file TGeoRCPtr.h.

operator=() [2/2]

template<class T >

TGeoRCPtr & TGeoRCPtr< T >::operator= ( T * ptr )

inline

Definition at line 88 of file TGeoRCPtr.h.

operator==() [1/2]

template<class T >

bool TGeoRCPtr< T >::operator== ( const T * ptr )

inline

Definition at line 111 of file TGeoRCPtr.h.

operator==() [2/2]

template<class T >

bool TGeoRCPtr< T >::operator== ( const TGeoRCPtr< T > & ptr )

inline

Definition at line 110 of file TGeoRCPtr.h.

Member Data Documentation

fPtr

template<class T >

T* TGeoRCPtr< T >::fPtr

private

Definition at line 114 of file TGeoRCPtr.h.