package pallina;

import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class EsercizioPallina extends JFrame{

    private Container c;
    private Pallina palla;
    private Thread t1;
    double x,y;
    private static final long serialVersionUID = 1L;
    private int xCentro=190, yCentro=190, raggio=20,raggioCG = 45;
    private double angolo = 0.00;

    public EsercizioPallina(){
        setVisible(true);
        setSize(400, 400);
        setResizable(false);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        c = getContentPane();

        palla = new Pallina();
        c.add(palla);

        t1 = new Thread(palla);
        t1.start();
    }

    class Pallina extends JPanel implements Runnable{
        public Pallina(){
            super();
            setBackground(Color.WHITE);
        }

        public void run() {
            while(true){
                repaint();
                try {
                    Thread.sleep(16);
                } catch(InterruptedException e) {
                    e.printStackTrace();
                }
                x = xCentro + Math.cos(angolo)*raggioCG;
                y = yCentro + Math.sin(angolo)*raggioCG;
                angolo= (angolo+0.1)%360;
            }
        }

        public void paintComponent(Graphics g) {
            super.paintComponent(g);
            g.setColor(Color.BLACK);
            g.fillOval((int)x-raggio, (int)y-raggio, raggio, raggio);

        }
    }

    public static void main(String[] args) {
        new EsercizioPallina();
    }
}