Design flaw, any ideas on how I should set up this class hierarchy?

[voidflux]

Hello everyone, I'm implementing a superclasss Vehicle and subclasses Car and Truck. I'm suppose to implement a method draw in the class RandomDrawing. This draw method can take in differne types of vehicles, and i'm painting a car and truck randomly on a screen multiple times. I alrady have everyhting coded and working right but I am rethinking my design. My design is, I have RandomDrawing as a superclass of Vehicle and Car and Truck are subclasses of vehicle. But really I don't see why RandomDrawing should even be part of the class hierarchy. Any ideas on how I can implement this so in my RandomDrawing class which extends jFrame can do the following:

public void paint(Graphics g)
{
Car c = new Car();
draw(c);
Truck t = new Truck();
draw(t);
}


Right now i have it set up as...


public void paint(Graphics g)
{
Car c = new Car();
c1.draw(jPanel1.getGraphics(),r.nextInt(sP.x),r.nextInt(sP.y));
Truck t = new Truck();
.
.
.

}


Thanks,


-Cory

[Phaelax]

Why can't you just make RandomDrawing a seperate class?


RandomDrawing r = new RandomDrawing();
Car c = new Car();

r.draw(c);


I don't really see the confusion. I think you're making things more difficult than you need to.

[voidflux]

Acutally now I got it to work so now i only have to put, draw(c1)....but now that you bring it up, that does make sense. I should just have RandomDrawing as a single class but when I tried to make the transformation, I get this error:

"RandomDrawing.java": paint(java.awt.Graphics) in car_and_truck.Vehicle cannot be applied to (java.awt.Graphics,int,int) at line 24, column 6

  public void draw(Vehicle v, int x, int y)
  {
   v.paint(jPanel1.getGraphics(), r.nextInt(sP.x),r.nextInt(sP.y));
  }

I got that error lasttime,but i fix it by creating a blank function called

public void paint(Graphics g, int x, int y)
{
//blank
}

But this isn't fixing the problem. Its not liking that I added 2 new params to the paint function.

Note: My Vechile/Car/Truck classes all have the function

public void paint(Graphics g, int x, int y);



Any idea's why this is? Thanks.

[Phaelax]

maybe you cannot override the paint() method? I dont know, I dont really mess with graphics in java a whole lot.

[voidflux]

I just left it as is, it works good and it seems like more over head to create a Random object each time you want to print a car or truck. This way you can just type in draw(car,...);

Thanks for the help though!