LibreOffice
LibreOffice 24.8 SDK C/C++ API Reference
Loading...
Searching...
No Matches
salhelper::SingletonRef< SingletonClass > Class Template Reference

template for implementing singleton classes. More...

#include <singletonref.hxx>

Public Member Functions

 SingletonRef ()
 standard ctor.
 
 ~SingletonRef ()
 standard dtor.
 
SingletonClass * operator-> () const
 Allows rSingle->someBodyOp().
 
SingletonClass & operator* () const
 Allows (*rSingle).someBodyOp().
 

Detailed Description

template<class SingletonClass>
class salhelper::SingletonRef< SingletonClass >

template for implementing singleton classes.

    Such classes can be instantiated every time they
    are needed. But the internal wrapped object will
    be created one times only. Of course it's used
    resources are referenced one times only too.
    This template hold it alive till the last
    reference is gone. Further all operations
    on this reference are threadsafe. Only
    calls directly to the internal object (which modify
    its state) must be made threadsafe by the object itself
    or from outside.
Attention
To prevent the code against race conditions, it's not allowed to start operations inside the ctor of the internal wrapped object - especially operations which needs a reference to the same singleton too.

The only chance to suppress such strange constellations is a lazy-init mechanism.

  • a) The singleton class can provide a special init() method, which must be called as first after creation.
  • b) The singleton class can call a special impl_init() method implicit for every called interface method.

Note further that this singleton pattern can work only, if all user of such singleton are located inside the same library! Because static values can't be exported - e.g. from windows libraries.

Constructor & Destructor Documentation

◆ SingletonRef()

template<class SingletonClass >
salhelper::SingletonRef< SingletonClass >::SingletonRef ( )
inline

standard ctor.

    The internal wrapped object is created only,
    if its ref count was 0. Otherwise this method
    does nothing ... except increasing of the internal
    ref count!

◆ ~SingletonRef()

template<class SingletonClass >
salhelper::SingletonRef< SingletonClass >::~SingletonRef ( )
inline

standard dtor.

    The internal wrapped object is removed only,
    if its ref count will be 0. Otherwise this method
    does nothing ... except decreasing of the internal
    ref count!

Member Function Documentation

◆ operator*()

template<class SingletonClass >
SingletonClass & salhelper::SingletonRef< SingletonClass >::operator* ( ) const
inline

Allows (*rSingle).someBodyOp().

◆ operator->()

template<class SingletonClass >
SingletonClass * salhelper::SingletonRef< SingletonClass >::operator-> ( ) const
inline

Allows rSingle->someBodyOp().


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