PUBLIC MEMBERS:  CLASSESSTRUCTSUNIONSENUMSTYPEDEFSMETHODSSTATIC METHODSDATASTATIC DATA
PRIVATE MEMBERS:  CLASSESSTRUCTSUNIONSENUMSTYPEDEFSMETHODSSTATIC METHODSDATASTATIC DATA

:: salhelper ::

template< typename SingletonClass >

class SingletonRef


Base Classes
None.
Known Derived Classes
None.

virtual abstract interface template
NO NO NO YES
Summary
template for implementing singleton classes.

    
Description
Such classes can be instanciated everytimes they
            are needed. But the internal wrapped object will
            be created one times only. Of course its 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, its not
                allowed to start operations inside the ctor
                of the internal wrapped object - especialy operations
                which needs a reference to the same singleton too.

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

                <ul>
                    <li>a) The singleton class can provide a special init()
                           method, which must be called as first after creation.</li>
                    <li>b) The singleton class can call a special impl_init()
                           method implicit for every called interface method.</li>
                </ul>
                
                Note further that this singleton pattern can work only, if
                all user of such singleton are located inside the same library!
                Because static values cant be exported - e.g. from windows libraries.
 
File
singletonref.hxx

Public Members

Methods


SingletonRef( );
standard ctor.

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

Private Members

Structs

SingletonLockInit creates an own mutex for guarding static contents.

Methods

::osl::Mutex &
ownStaticLock( ) const;

Static Data

SingletonClass * m_pInstance; pointer to the internal wrapped singleton.
sal_Int32 m_nRef; ref count, which regulate creation and removing of m_pInstance.

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