How to scan an object in java?

Question

I am making exactly the same Java program that is in this link:

Run-time Polymorphism in Java without "abstract"?

But I am having problems in the Main Application.

In my problem I have to ask the user to enter which types does he want(Bicycle,MountainBike,RoadBike).

And then I add what type he chose to an array of 5 indexes.

How can I do that?

Please give me some help.

Thanks in advance.

score 0 · Answer 1 · answered Dec 09 '12 at 13:05

I don't know how you look for answers from your users, but if it's buttons you do it with, you can just add the requested type of object, when a user press specific buttons.

But what you have to do, is make an ArrayList<Bicycle> and then just add the objects that extends Bicycle.

score 0 · Answer 2 · answered Dec 09 '12 at 13:11

You should create a factory method that returns an instance of a Bicycle:

For example:

public Bicycle createBicycle(String type) {
    if (type.equals("Bicycle")) {
        return new Bicycle(20, 10, 1);
    } else if (type.equals("MountainBike")) {
        return new MountainBike(20, 10, 5, "Dual");
    }
    //and so on..
}

And use it like this for example:

Bicycle[] bicycles = new Bicycle[5];
bicycle[0] = createBicycle("Bicycle");

How to scan an object in java?

2 Answers2