package gradebook; import people.*; import java.util.*; /** *This class collects all the various components of the grader: Instructor, TA and Student Views. **/ public abstract class Gradebook { /** *The courses associated with this gradebook. */ public Collection courses; /** *The Instructor associated with this gradebook. *No limits on permissions. */ public Instructor instructor; /** *Set Instructor associated with this gradebook. *pre: * instructor.equals(null); */ public abstract void setInstructor(Instructor ins); /** *Add courses to collection associated with this gradebook. *pre: * !courses.contains(cor); */ public abstract void addCourse(Course cor); }