This class is used as a base class for a set of Segment list managment classes. A default constructor that initializes data members to default values. A Copy constructor. Note that the derived class should take care of managing the segments list. Cause the list to be deleted.
Derived class manages the list.
Get the list's startTime. Sum the startTime, and each duration for each segment to determine the list's stopTime. Return the current number of segments in the list. Return the duration of the segment at index specified. Implemented by derived classes.