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Thread: Subclasses in Superclass array

  1. #1
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    Default Subclasses in Superclass array

    I have a superclass (Student) and two subclasses (RStudent and CStudent) that inherit from Student. I want to be able to have one ArrayList of both RStudent and CStudent. I tried just using ArrayList<Student> students = new Arraylist<>(); but I cant access any variables that are specific to the subclasses. For example if I use students.add(newCStudent), when I try use students.get(0).mark (which is a variable only in CStudent) it doesn't work. How can I do this?

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    Default Re: Subclasses in Superclass array

    it doesn't work. How can I do this
    Cast the value from the List to the subclass it is to make its contents available.

    Why are the subclasses mixed together in the List if you want to treat them as subclasses instead of strictly accessing them with superclass methods?
    If you don't understand my answer, don't ignore it, ask a question.

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