Mine

import java.awt.Graphics;

import java.util.Timer;

import java.util.TimerTask;



import javax.swing.JPanel;



public class Circulo extends JPanel {

	/**

	 * 

	 */

	private static final long serialVersionUID = 6787599365941305525L;



	private int choice;



	public int x, y = 1;



	private int contador = 0;



	private Timer timer;



	public Circulo(int userChoice, int x2, int y2) {

		choice = userChoice;

		x = x2;

		y = y2;

	}



	public void paintComponent(final Graphics g) {

		int intervalo = 250;

		final Circulo objCirculo = this;



		super.paintComponent(g);



		if (null == this.timer) {

			this.timer = new Timer();

			this.timer.scheduleAtFixedRate(new TimerTask() {

				@Override

				public void run() {

					objCirculo.repaint();

				}

			}, intervalo / 2, intervalo);

		}



		switch (choice) {

		case 1:

			g.drawOval(10 + x * 10, 10 + y * 10, 50 + x * 10, 50 + y * 10);

			break;

		case 2: {

			int[] p = { 0, 0, getWidth(), getHeight() };

			int passo = 20;

			int r = Math.min(getWidth(), getHeight()) / passo / 2;



			int i = 1 + (contador % passo);



			g.drawOval((p[2] / 2) - r * i, (p[3] / 2) - r * i, 2 * r * i, 2 * r

					* i);



			contador++;

			break;

		}

		}



	}

}