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Java

Chris Smith
Chris Smith
547 Points
Posted by Chris Smith
Chris Smith
547 Points

Objects from Classes

Hi,

I understand I need to create an object from a class. Though I don't understand why I need to pass variables into it when I'm creating it.

Below is the code which defines the go karts 'Name'. Couldn't I just leave the name out of it when creating the object and define the go karts 'Name' in another piece of code. Wouldn't this be better?

GoKartClass Kart = new GoKartClass("T300 L2");

System.out.printf("%s \n",Kart.isWheelCount());

I've reused the object to get the 'WheelCount' though this piece of code has nothing to do with the go karts 'Name'.

I'm just a bit confused.

Thanks, Chris

gareth o'connor
gareth o'connor
1,755 Points
gareth o'connor
gareth o'connor
1,755 Points

You can have multiple constructors in each class. By adding a 'no argument' constructor you can achieve what you want:

public class GoKartClass {

    private String name = '';

// this is the no argument constructor
    public GoKartClass () {
    }

// this is probably similar to your existing constructor
    public GoKartClass (String name) {
        this.name = name;
    }
}

You can then create a new kart object with or without a name:

GoKartClass Kart = new GoKartClass();

or 

GoKartClass Kart = new GoKartClass("T300 L2");

1 Answer

Chris Smith
Chris Smith
547 Points
Chris Smith
Chris Smith
547 Points

Thanks for explaining it to me, you've been most helpful.

Chris