Set/Get Methods for Private Fields in Super/Sub classes

Question

So basically I have a superclass of a Geometric Figure that has private fields, say length and width. I have a subclass of a Rectangle that has a length and width in the constructor.

In the subclass, I must include a method to set the length and width of the Rectangle to the length and width of the private fields of the Geometric Figure. How do I do this?

Thanks

EDIT: For example:

public class GeometricFigure{
private double length;
private double width;
}

public class Rectangle extends GeometricFigure{
     public Rectangle(int length, int width){}
//set and get methods here to set the private fields to the variables in the parameter
}

Not yet. Basically I need to have the code for the problem in the subclass, not superclass. — noobforce, Nov 24 '14 at 13:43
Remember one thing bro, you can't access private members of a class directly from outside that class until you use Reflection! — Sarthak Mittal, Nov 24 '14 at 13:46
@noobforce Reflection provides access to the bytecode, and so does some funny (or messy, depends of the point of view) thing on runtime. But if you're learning Java basics, I don't think your teacher want you to do this ;) (more information [on this question](http://stackoverflow.com/questions/37628/what-is-reflection-and-why-is-it-useful)) — NiziL, Nov 24 '14 at 13:53

brso05 · Accepted Answer · 2014-11-24T16:26:51.740

0

You can create getter and setter methods in the superclass like:

public GeometricFigure(int length, int width)
{
     this.length = length;
     this.width = width;
}

public Rectangle(int length, int width)
{
    super(length, width);
}

Your 2 constructors could look like this.

edited Nov 24 '14 at 16:26

answered Nov 24 '14 at 13:32

brso05

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I'm not supposed to do it like that. My teacher says the superclass cannot have any methods. – noobforce Nov 24 '14 at 13:39
Then add them to superclass constructor – brso05 Nov 24 '14 at 13:40
Apparantly the constructor in the superclass is supposed to be empty. – noobforce Nov 24 '14 at 13:42
1

@noobforce No way to do what you are asking unless you make attributes in superclass public or protected. – brso05 Nov 24 '14 at 13:44
Meh. I'll just do what you said and look at it later. Thanks. – noobforce Nov 24 '14 at 13:46
(hoping that someone sees this) I tried doing what you typed in the code, but I still get the error that I cannot access the private field because it is private... – noobforce Nov 24 '14 at 16:18
@noobforce sorry I gave you the wrong syntax it should just be `super(length, width);` in your subclass constructor. – brso05 Nov 24 '14 at 16:27

score 0 · Answer 2 · answered Nov 24 '14 at 13:33

0

You have a few options,

Provide constructor in super class which accepts width and length. Subclass will use it
Provide setter/getter method in super class which accepts width and length, just use it in the subclass

Otherwise you have no access to set private fields. (except reflection)

answered Nov 24 '14 at 13:33

Orhan Obut

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Would I need to use a super() call or anything like that? – noobforce Nov 24 '14 at 13:37
if the constructor is in super class yes, you need to call super, if you use the methods, just make them protected so you can just call them – Orhan Obut Nov 24 '14 at 13:38

Set/Get Methods for Private Fields in Super/Sub classes

2 Answers2