C++ Adapter

The adapter pattern "adapts" one class to another.

To see the value imagine that you only have access to 
binaries for DanceJudges and Person classes.



This is a class that uses the IDanceFilter interface.
-----------------------------------------------------
class DanceJudges{
public:
	bool canDance(IDanceFilter* iDanceFilter);
};

bool DanceJudges::canDance(IDanceFilter* iDanceFilter){
return iDanceFilter->canDance();
}

-----------------------------------------------------


This is a class that does not implemnt the IDanceFilter 
interface.
-----------------------------------------------------
class Person{
public:
	Person(int grace);
	int graceLevel;
}; 

Person::Person(int grace){
	Person::graceLevel = grace;
}
-----------------------------------------------------


Here is the interface.
-----------------------------------------------------
class IDanceFilter{
public:
	virtual ~IDanceFilter(){};
	virtual bool canDance() = 0;
};
-----------------------------------------------------


This is the adapter class. This class will enable the
DanceJudges class to use the Person class as if it had
implemented the IDanceFilter interface.
-----------------------------------------------------
class PersonAdapter : public IDanceFilter{
public:
	PersonAdapter(Person* person);
	bool canDance();
private:
	Person* person;
};

PersonAdapter::PersonAdapter(Person* person){
	PersonAdapter::person = person;
}

bool PersonAdapter::canDance(){
	if(PersonAdapter::person != 0 
		&& PersonAdapter::person->graceLevel > 13){
		return true;}
	else
		return false;
}
-----------------------------------------------------


Test stub to show it all work.
-----------------------------------------------------
int main(){
	std::cout<<"main: START\n";

	DanceJudges danceJudges;
	Person* person = new Person(14);	
	IDanceFilter* iDanceFilter = new PersonAdapter(person);

	if(danceJudges.canDance(iDanceFilter))
		std::cout<<"they can dance\n";
	else
		std::cout<<"they can NOT dance\n";
	
	std::cout<<"main: END\n";

	//QUESTION
	delete person;
	delete iDanceFilter;
	return 0;
}
-----------------------------------------------------


Here is a tar with the above java classes in it. 
C++_adapter.tar