import java.awt.Graphics;
import java.util.ArrayList;
public class Balls {
double x = 100;
double y = 10;
double dx = 10;
double dy = 0;
double dt = 0.2;
double u = 0.9;
double g = 15;
public void move(int height, int width) {
if (y == height - 30) {
dx *= u;
}
if (y > height - 30) {
y = height - 30;
dy *= u;
dy = -dy;
} else {
dy += dt * g;
y += dy * dt + 0.5 * g * dt * dt;
}
if (x > width - 30) {
x = width - 30;
dx = -dx;
} else if (x < 0) {
x = 0;
dx = -dx;
} else {
x += dx;
}
}
public void draw(Graphics g) {
g.fillOval((int) x, (int) y, 30, 30);
}
}