Lazy initialization

http://en.wikipedia.org/wiki/Lazy_initialization

from GoF:

You can avoid this by being careful to access products solely through accessor operations that create the product on demand. Instead of creating the concrete product in the constructor, the constructor merely initializes it to 0. The accessor returns the product. But first it checks to make sure the product exists, and if it doesn't, the accessor creates it. This technique is sometimes called lazy initialization. The following code shows a typical implementation:

class Creator {
public:
Product* GetProduct();
protected:
virtual Product* CreateProduct();
private:
Product* _product;
};

Product* Creator::GetProduct () {
if (_product == 0) {
_product = CreateProduct();
}
return _product;




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Atte.

German Gonzalez