Derive abstract class from non-abstract class
- by Jehof
Is it OK to derive an abstract class from a non-abstract class or is there something wrong with this approach?
Here´s a little example:
public class Task {
// Some Members
}
public abstract class PeriodicalTask : Task {
// Represents a base class for task that has to be done periodicaly.
// Some additional Members
}
public class DailyTask : PeriodicalTask {
// Represents a Task that has to be done daily.
// Some additional Members
}
public class WeeklyTask : PeriodicalTask {
// Represents a Task that has to be done weekly.
// Some additional Members
}
In the example above i do not want to make the class Task abstract, because i want to instantiate it directly. PeriodicalTask should inherit the functionality from Task and add some additional members but i do not want to instantiate it directly. Only derived class of PeriodicalTask should be instantiated.