LACS03_BallRunner.java

/**
BallRunner.java     MrG 2012.0531
purpose:    animate a bouncing ball
required:   BallRunner.java         main class
        Ball.java           derived class
        StdDraw.java            graphics class
translator: javac BallRunner.java
interpreter:    java BallRunner N
*/
public class BallRunner
{
    public static void main(String[] args)
    {
        int N = Integer.parseInt(args[0]);
        Ball[] balls = new Ball[N];
        for(int i=0;i<N;i++)
        {
            balls[i] = new Ball();
        }
        StdDraw.setCanvasSize(900,900);
        StdDraw.setXscale(-10.0,+10.0);
        StdDraw.setYscale(-10.0,+10.0);
        while(true)
        {
            StdDraw.clear(StdDraw.GRAY);
            for(int j=0;j<N;j++)
            {
                balls[j].move();
                balls[j].draw();
            }
            StdDraw.show(10);
        }
    }
}