Java dynamic number after variable

Question

In java i need to create dynamic bouncingBall. like this

BouncingBall bal
BouncingBall bal2
BouncingBall bal3

I'm trying to do this with a while loop:

// Create dynamich numbers of balls
int zero = 1;

while(zero < nrOfBalls)
{
    BouncingBall ball + zero = new BouncingBall(50, 50, 16, Color.BLUE, ground, myCanvas);
    ball.draw();
    zero++;
}

But is still saying that the +zero varbariable is not good. Could somebody help me!

@param nrOfBalls is the number what the users enters if nrOfBalls is 4 than the while loop must create 4 balls.

What is `BouncingBall ball + zero` supposed to mean? It's not a valid syntax. — Eran, Sep 03 '14 at 15:05
the ball needs increment like this: ball, ball2 ball2. When i do this manualy it works. But now it must be dynamic — Bham, Sep 03 '14 at 15:06
use an arraylist and the index as new variable or dynamic allocation of memory .... — StackFlowed, Sep 03 '14 at 15:07

score 2 · Answer 1 · answered Sep 03 '14 at 15:07

2

If you wish to have multiple BouncingBall variables, use an array.

BouncingBall[] balls = new BouncingBall[nrOfBalls];
int count = 0;
while(count< nrOfBalls)
{
    balls[count] = new BouncingBall(50, 50, 16, Color.BLUE, ground, myCanvas);
    balls[count].draw();
    count++;
}

answered Sep 03 '14 at 15:07

Eran

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Good solution, just extra info for poster: dynamic variable names do not exist in Java, and most of the time when you see yourself wanting to use these, either use an array (this is usually better and offers more functionality), or you should concider if you are trying to solve your problem in the right way. (since, if you think about it, using dynamic variable names is quite error prone, since you have no way of checking how many variables actually excist (edit: everything is ofcourse possible with reflection.. but lets not start on that :P)) – Pienterekaak Sep 03 '14 at 15:30

Java dynamic number after variable

1 Answers1