Inheritance diagram

Description

This class has the reference counting mechanism which is similar to the mechanism that the SFYResponder class and the SFBBase class have.

This class object works as a smart pointer by becoming a parameter of the SFXRefObjectPointer class.

The SFMTYPEDEFREFOBJECT macro defines class name aliases (ClassNameSmp etc.) of SFXRefObjectPointer<ClassName>, and help you use the smart pointer feature easily.

// Type alias macro of the reference counting object class name.
SFMTYPEDEFREFOBJECT(MyRefObject)

class MyRefObject: public SFORefObject {
    // Macro to prohibit the developer from copying this instance
    SFMSEALCOPY(MyRefObject)

    // Macro to specify the inheritance relation from the SFORefObject class to this class
    SFMREFOBJECTINSTANTIATEONE(MyRefObject, SFORefObject)

    public:

        // Generate a MyRefObject class smart pointer.
        static  MyRefObjectSmp      NewInstance      (SFCErrorPtr exception = null);

    protected:
        explicit                    MyRefObject      (Void);
        virtual                     ~MyRefObject     (Void);

        // Initialization function which has the possiblity to raise an error
        virtual SFCError            Initialize       (Void);
};

// Constructor 
MyRefObject::MyRefObject(Void)
{
}

// Destructor
MyRefObject::~MyRefObject(Void)
{
}

// Generate a MyRefObject class smart pointer
MyRefObjectSmp MyRefObject::NewInstance(SFCErrorPtr exception)
{
    return static_pointer_cast<MyRefObject>(Factory(::new MyRefObject, exception));
}

// Initialization function which has the possiblity to raise an error
// This function is called by the Factory() function
SFCError MyRefObject::Initialize(Void)
{
    SFCError error;

    // Call the parent's initialization function
    if ((error = SFORefObject::Initialize()) == SFERR_NO_ERROR) {

        // MyRefObject specific initialization
        error = // (..ommited..);

    }
    return error;
}

Reference

SFXRefObjectPointer

Member

Argument

Return value

Description

This function is used to implement the NewInstance function which is necessary to define the concrete class of a object class newly.

With this function, the NewInstance function for the concrete class of a object class can be implemented easily.

	Note
	The SFORefObject::Factory() function makes the initialization by internal calling the SFORefObject::Initialize function. Initialization code which may raise an error should be written in the SFORefObject::Initialize function.

	static_pointer_cast operator
	Since the SFORefObject::Factory function returns the value of the SFORefObjectSmp type, it is necessary to downcast it into the type of the newly created object class with the static_pointer_cast operator.

Example

The following is the code to implement the NewInstance() function and the Initialize() function of the MyTableCellReactor class.

/*public */MyTableCellReactor MyTableCellReactor::NewInstance(SFCErrorPtr exception)
{
    return static_pointer_cast<MyTableCellReactor>(Factory(::new MyTableCellReactor, exception));
}// MyTableCellReactor::NewInstance //

/*protected virtual */SFCError MyTableCellReactor::Initialize(Void)
{
    SFCError                                    error;

    // Call the parent's initialize function
    if ((error = SFOTableCellReactor::Initialize()) == SFERR_NO_ERROR) {

        // Initialization code which may raise an error
        // ..(ommited)..

    }
    return error;
}// MyTableCellReactor::Initialize //

Internal implementation of the SFORefObject::Factory function is as follows:

/*protected static */SFORefObjectSmp SFORefObject::Factory(SFORefObjectPtr object, SFCErrorPtr exception)
{
    SFCError                                    error(SFERR_NO_ERROR);
    SFORefObjectSmp                             result;

    if (object != null) {
        if ((error = object->Initialize()) == SFERR_NO_ERROR) {
            result.Set(object, false);
        }
    }
    else {
        error = SFERR_NO_MEMORY;
    }
    if (exception != null) {
        *exception = error;
    }
    return result;
}// SFORefObject::Factory //

Reference

SFORefObject::Initialize

Description

This function makes the initialization which may raise an error.

This function is called by the SFORefObject::Factory function.

If a concrete class specific initialization code may raise an error, you must override this function. Usually, the parent's Initialize() function should be called first in the implementation.

Example

See the example of the SFORefObject::Factory function.

Reference

SFORefObject::Factory