Random question

[Isaac Hewitt]

I am doing a program where I use a JWindow as sticky notes. I give each note and ID using code like this.

 
int ID = new Random().nextInt();

When I run some tests I get some of the ID numbers printed with a minus sign preceding the number. I would like to be able to not have a minus sign there. What should I do. Thanks.

[Garrett Rowe]

int ID = Math.abs(new Random().nextInt());
//OR
int ID2 = new Random().nextInt(Integer.MAX_VALUE);

The real question is why are you using a random number generator to assign an ID? What happens if you happen to assign the same ID to two different objects.
[ July 19, 2008: Message edited by: Garrett Rowe ]

[Rob Spoor]

I agree with Garrett. A better approach would be to use a static field:

public class StickyNotes
{
    private static int nextID = 1;
 
    public static synchronized int getNextID()
    {
        return nextID++;
    }
}

Note that I made the method synchronized to make sure that the increase is atomic.