Arraylist for subclasses

Question

I have a Vehicle superclass and then I have some subclasses to that one. I am trying to have an array list that adds objects from all of the subclasses into the same list, but I'm coming up short.

I currently have the list in my program class but I have moved it around a bit.

This is the code I have in Program:

ArrayList<Vehicles> Inventorie = new ArrayList<>();

public void setInventorie(Car newCar) {
    Inventorie.add(newCar);
}

And this the code I have in Car:

public void addCar(){
    System.out.println("Make: ");
    Make = scan.nextLine();
    System.out.println("RegNr");
    regNr = scan.nextInt();
    System.out.println("Year");
    year = scan.nextInt();
    setValue();
    Car c1 = new Car(make, regNr, Year);
     Program.setInventorie(c1);
}

In Car I am getting "Non-static method 'setInventorie(Project1.Vehicles)' cannot be referenced from static context."

I also had to comment out the main method or the compiler couldn't resolve the symbol Inventorie (name of array list).

Tried to explain my problem as best as I could, hope someone can help. And yes, I am new to this so it might seem really stupid but it's the best I could do.

Thanks

You should study the [difference between static methods and instance methods](http://stackoverflow.com/questions/11993077/difference-between-static-methods-and-instance-methods). You defined `setInventorie()` as an instance method but you're using it as a class (static) method. That's not allowed in Java — Oneiros, Apr 04 '17 at 10:53
And read about java naming conventions. Only class names or constants start with UpperCase; variables go carInventory always ... — GhostCat, Apr 04 '17 at 10:55

Steve Smith · Accepted Answer · 2017-04-04T10:57:26.570

0

I'm guessing it's the line Program.setInventorie(c1);. You need to create an instance of the Program class and call setInventorie() on that. setInventorie() is not a static method.

e.g.:

Program myProgram = new Program();
myProgram.setInventorie(c1);

edited Apr 04 '17 at 10:57

answered Apr 04 '17 at 10:53

Steve Smith

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I didn't post all the code but I have that in Program: Car c1 = new Car(); – brodude Apr 04 '17 at 10:54
You didn't spend much time learning the basic stuff. Just turn to the duplicated question I linked to. – GhostCat Apr 04 '17 at 10:55
@brodude, see my answer: "You need to create an instance of the **Program** class and call setInventorie() on that." – Steve Smith Apr 04 '17 at 10:56
Not quite sure how it is the same. The answers in that thread says create an instance and my post you replied to said I have an instance? – brodude Apr 04 '17 at 11:01
@SteveSmith Thanks, I did that now but I'm still getting the non-static error message. – brodude Apr 04 '17 at 11:02
Update the question with your new code. – Steve Smith Apr 04 '17 at 11:04
Sorry, I did it wrong the first time. Your solution worked. Big thanks! – brodude Apr 04 '17 at 11:07

Arraylist for subclasses

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