SharedResource< T > Class Template Reference

SharedResource is a pattern that allocates only one instance of a class, with reference counting. SharedResource instance is automatically allocated/freed when needed. More...

Detailed Description

template<class T>
class ConceptRT::SharedResource< T >

SharedResource is a pattern that allocates only one instance of a class, with reference counting. SharedResource instance is automatically allocated/freed when needed.

Example :

class Example: public SharedResource<Example>
{
public:

private:                                  // Mandatory
  Example() { }                           // Mandatory
  friend class SharedResource<Example>    // Mandatory
};

Warning

Constructor must be declared in private and the parent class must be friend.

Inheritance diagram for SharedResource< T >:

Static Public Member Functions
static T *	AcquirePointer ()
	Allocates the resource if needed, and increments the reference count by 1. More...
static T &	Acquire ()
	Allocates the resource if needed, and increments the reference count by 1. More...
static T *	GetResourcePointer ()
	Get the pointer on the currently allocated resource. More...
static T &	GetResource ()
	Get the currently allocated resource. More...
static void	Release ()
	Releases the shared ressource. More...

Methods Documentation

T & Acquire ( )

static

Allocates the resource if needed, and increments the reference count by 1.

Returns

The resource.

Warning

Non-Deterministic: May create the ressource if not yet created. Determinism when using ConceptRT library can be ensure by using Context Time Critical mechanisms.

RT Exceptions:

RT_ERROR_NEW_INSTANCE_NOT_ABLE_TO_CREATE

RT_ERROR_SHARED_RESSOURCE_REFERENCE_COUNT_MISSMATCH

T * AcquirePointer ( )

static

Allocates the resource if needed, and increments the reference count by 1.

Returns

The pointer on resource.

Warning

Non-Deterministic: May create the ressource if not yet created. Determinism when using ConceptRT library can be ensure by using Context Time Critical mechanisms.

RT Exceptions:

RT_ERROR_NEW_INSTANCE_NOT_ABLE_TO_CREATE

RT_ERROR_SHARED_RESSOURCE_REFERENCE_COUNT_MISSMATCH

T & GetResource ( )

static

Get the currently allocated resource.

Returns

The resource.

Warning

Call order dependence : Should be called only after the SharedResource is Acquired. Don't forget to release the ressource after usage.

RT Exceptions:

RT_ERROR_SHARED_RESSOURCE_REFERENCE_COUNT_MISSMATCH

T * GetResourcePointer ( )

static

Get the pointer on the currently allocated resource.

Returns

The pointer on resource.

Warning

Call order dependence : Should be called only after the SharedResource is Acquired. Don't forget to release the ressource after usage.

RT Exceptions:

RT_ERROR_SHARED_RESSOURCE_REFERENCE_COUNT_MISSMATCH

void Release ( )

static

Releases the shared ressource.

Resource is freed when reference counting reaches 0.

Warning

Non-Deterministic: May delete the ressource if there is no references anymore on it. Determinism when using ConceptRT library can be ensure by using Context Time Critical mechanisms.

RT Exceptions:

RT_ERROR_SHARED_RESSOURCE_REFERENCE_COUNT_MISSMATCH

RT_ERROR_INTERNAL_DELETE_A_NON_NULL_OBJECT