Pluggable Selector

Pluggable Selector ¶

�� 간��게 Pluggable Behavior�� 구�� . �� , �� .

~cpp 
class ListPane
{
public:
	Type printElement(Object& anObject) {
		return anObject.printString();
	}
};

class DollarListPane : public ListPane
{
public:
	Type printElement(Object& anObject) {
		return anObject.asDollarFormatString();
	}
};

class DiscriptionListPane : public ListPane
{
public:
	Type printElement(Object& anObject) {
		return anObject.desription();
	}
};

�� 계�� . �� 결�� ListPane �� 게 �� . �� 게 �� .

~cpp 
class ListPane
{
private:
	void (ListPane::*printMessage)();
public:
	Type printElement(Object& anObject) {
		return anObject.perform(printMessage);
	}
	void initialize() {
		printMessage = printString;	// printString��� ����������� 구��������� ������.
	}
};

�� : 그�� .
�� : P.S�� 객�� 구�� .
�� : �� 까�� . �� 그�� . �� 고 �� State Object�� .

�� selector�� . �� Message�� . selector�� 기 ��게 �� Composed Method�� .

�� , �� 고 ��, �� Pluggable Selector�� .(???)

~cpp 
class RelativePoint
{
public:
	static RelativePoint* centered(Figure& aFigure) {
		RelativePonit* rp = new RelativePoint;
		rp->setFigurenMessage(aFigure, center);		
	}
	void setFigurenMessage(Figure& aFigure, int aSymbol()) {
		figure = aFigure;
		locationMessage = aSymbol;
	}
};

�� Point�� .

~cpp 
Point RelativePoint::asPoint()
{
	return figure.perform(locationMessage);
}

Point RelativePoint::x()
{
	return asPoint().x();
}

�� CenteredRelativePoint, TopLeftRelativePoint�� . �� center�� , topLeft�� .

SBPPSummary