Question

I have this:

public class Sprite

{
    protected float x;
    protected float y;
    protected Image image;
    protected Rectangle boundingBox;


    public Rectangle getBoundingBox()
    {
         boundingBox = new Rectangle(x, y,
                    image.getWidth(), image.getHeight());
        return boundingBox;
    }

However I get a null pointer exception when I run it. The class sprite is never used by itself, only used as a superclass.

The only way for image to be defined is through the constructor:

Sprite(float x, float y, Image image) {
    this.x = x;
    this.y = y;
    this.image = image;
}

Answer 1

Probably because the variable image is never initialized. Therefore image.getWidth() and image.getHeight() will fail with NullPointerExceptions. Either initialize the variable. Or pass in image or check for null before you attempt to use it.