The Response for Class metric
The Response for Class (RFC) metric is the total number of methods that can potentially be executed in response to a message received by an object of a class. This number is the sum of the methods of the class, and all distinct methods are invoked directly within the class methods. Additionally, inherited methods are counted, but overridden methods are not, because only one method of a particular signature will always be available to an object of a given class.
Note
The Response Set (RS) of a class is a set of methods that can potentially be executed by an object of that class. RFC is the count of these methods belonging to the set.
Notice that a given method is counted only once even if it is invoked many times in the call graph as a response to a message. Classes with high RFC are more complex and prove to be difficult to debug and test, because of high cross-object communication and higher variance in the potential responses and call graphs, as responses to...
