import java.awt.*;
import javax.swing.*;

/* <applet code="Guruguru10.class" width="200" height="150"> </applet> */

public class Guruguru10 extends JApplet implements Runnable {
  int r = 50, x = 110, y = 70;
  double theta = 0; // 角度
  Thread thread = null;

  @Override
  public void paint(Graphics g) {
    super.paint(g); // スーパークラスのpaintを呼び出す
                    // 全体を背景色で塗りつぶす。
    g.drawString("Hello, World!", x, y);
  }

  @Override
  public void start() {
    if (thread == null) { // 念のためチェック
      thread = new Thread(this);
      thread.start();
    }
  }

  @Override
  public void stop() {
    thread = null;
  }

  public void run() {
    Thread thisThread = Thread.currentThread();
    for (; thread == thisThread; theta += 0.02) {
      x = 60 + (int)(r * Math.cos(theta)); y = 70 - (int)(r * Math.sin(theta));
      repaint();  // paintを間接的に呼出す
      try {
        Thread.sleep(10); // 10 ミリ秒お休み
      } catch (InterruptedException e) {}
    }
  }

  public static void main(String[] args) {
    JFrame frame = new JFrame("ぐるぐる!");
    JApplet applet = new Guruguru10();
    applet.setPreferredSize(new Dimension(200, 150));
    frame.add(applet);
    frame.pack();
    frame.setVisible(true);
    applet.init();
    applet.start();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }
}