This example shows an applet implementation of the Dining Philosophers problem.

Java Code:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.URL;

import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

public class DiningPhilosophers extends javax.swing.JApplet implements
    ActionListener, ChangeListener {

  private JButton stopStartButton = new JButton("start");

  // delays can go from 0 to 10,000 milliseconds, initial value is 500
  int grabDelay = 500;

  private JSlider grabDelaySlider = new JSlider(JSlider.HORIZONTAL, 0, 100, 5);

  private JLabel label = new JLabel("  500 milliseconds");

  private JPanel philosopherArea;

  public ImageIcon[] imgs = new ImageIcon[3];

  Chopstick[] chopsticks = new Chopstick[NUMPHILS];

  String[] names = { "Arisduktle", "Dukrates", "Pythagoduke", "Duko",
      "Dukimedes" };

  static final int NUMPHILS = 5;

  static final int HUNGRYDUKE = 0;

  static final int RIGHTSPOONDUKE = 1;

  static final int BOTHSPOONSDUKE = 2;

  private int width = 0;

  private int height = 0;

  private double spacing;

  private static final double MARGIN = 10.0f;

  private Philosopher[] philosophers = new Philosopher[NUMPHILS];

  public void init() {

    imgs[HUNGRYDUKE] = new ImageIcon(getURL("images/hungryduke.gif"));
    imgs[RIGHTSPOONDUKE] = new ImageIcon(
        getURL("images/rightspoonduke.gif"));
    imgs[BOTHSPOONSDUKE] = new ImageIcon(
        getURL("images/bothspoonsduke.gif"));

    width = imgs[HUNGRYDUKE].getIconWidth() + (int) (MARGIN * 2.0);
    height = imgs[HUNGRYDUKE].getIconHeight() + (int) (MARGIN * 2.0);
    spacing = width + MARGIN;

    GridBagLayout gridBag = new GridBagLayout();
    GridBagConstraints c = new GridBagConstraints();

    JPanel contentPane = new JPanel();
    contentPane.setLayout(gridBag);

    philosopherArea = new JPanel(null);
    philosopherArea.setBackground(Color.white);
    Dimension preferredSize = createPhilosophersAndChopsticks();
    philosopherArea.setBorder(BorderFactory.createCompoundBorder(
        BorderFactory.createLoweredBevelBorder(), BorderFactory
            .createEmptyBorder(5, 5, 5, 5)));
    philosopherArea.setPreferredSize(preferredSize);

    c.fill = GridBagConstraints.BOTH;
    c.weighty = 1.0;
    c.gridwidth = GridBagConstraints.REMAINDER; //end row
    gridBag.setConstraints(philosopherArea, c);
    contentPane.add(philosopherArea);

    c.fill = GridBagConstraints.HORIZONTAL;
    c.weightx = 1.0;
    c.weighty = 0.0;
    gridBag.setConstraints(stopStartButton, c);
    contentPane.add(stopStartButton);

    c.gridwidth = GridBagConstraints.RELATIVE; //don't end row
    c.weightx = 1.0;
    c.weighty = 0.0;
    gridBag.setConstraints(grabDelaySlider, c);
    contentPane.add(grabDelaySlider);

    c.weightx = 0.0;
    c.gridwidth = GridBagConstraints.REMAINDER; //end row
    gridBag.setConstraints(label, c);
    contentPane.add(label);
    contentPane.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
    setContentPane(contentPane);

    stopStartButton.addActionListener(this);
    grabDelaySlider.addChangeListener(this);

  }

  public void actionPerformed(ActionEvent e) {
    if (stopStartButton.getText().equals("stop/reset")) {
      stopPhilosophers();
      stopStartButton.setText("start");
    } else if (stopStartButton.getText().equals("start")) {
      startPhilosophers();
      stopStartButton.setText("stop/reset");
    }
  }

  public void stateChanged(ChangeEvent e) {
    JSlider source = (JSlider) e.getSource();
    grabDelay = source.getValue() * 100;
    label.setText(String.valueOf(grabDelay + " milliseconds"));
  }

  public void startPhilosophers() {
    for (int i = 0; i < NUMPHILS; i++)
      philosophers[i].philThread.start();
  }

  public void stopPhilosophers() {
    for (int i = 0; i < NUMPHILS; i++)
      philosophers[i].philThread.interrupt();
  }

  public Dimension createPhilosophersAndChopsticks() {
    double x, y;
    double radius = 80.0;
    double centerAdj = 85.0;
    double radians;

    Dimension preferredSize = new Dimension(0, 0);

    /*
     * for a straight line y = MARGIN;
     */
    for (int i = 0; i < NUMPHILS; i++)
      chopsticks[i] = new Chopstick();

    for (int i = 0; i < NUMPHILS; i++) {
      /*
       * for a straight line x = i * spacing;
       */
      radians = i * (2.0 * Math.PI / (double) NUMPHILS);
      x = Math.sin(radians) * radius + centerAdj;
      y = Math.cos(radians) * radius + centerAdj;
      philosophers[i] = new Philosopher(this, i, imgs[HUNGRYDUKE]);
      philosophers[i].setBounds((int) x, (int) y, width, height);
      philosopherArea.add(philosophers[i]);
      if ((int) x > preferredSize.width)
        preferredSize.width = (int) x;
      if ((int) y > preferredSize.height)
        preferredSize.height = (int) y;
    }

    preferredSize.width += width;
    preferredSize.height += height;
    return preferredSize;
  }

  protected URL getURL(String filename) {
    URL codeBase = getCodeBase();
    URL url = null;

    try {
      url = new URL(codeBase, filename);
    } catch (java.net.MalformedURLException e) {
      System.out.println("Couldn't create image: "
          + "badly specified URL");
      return null;
    }

    return url;
  }
}

/*
 * This class requires no changes from the 1.0 version. It's kept here so the
 * rest of the example can compile.
 */

class Philosopher extends JLabel implements Runnable {
  private Chopstick leftStick, rightStick;

  private boolean sated;

  private DiningPhilosophers parent;

  private int position;

  Thread philThread = null;

  public Philosopher(DiningPhilosophers parent, int position, ImageIcon img) {
    super(parent.names[position], img, JLabel.CENTER);

    this.parent = parent;
    this.position = position;

    setVerticalTextPosition(JLabel.BOTTOM);
    setHorizontalTextPosition(JLabel.CENTER);

    // identify the chopsticks to my right and left
    this.rightStick = parent.chopsticks[position];
    if (position == 0) {
      this.leftStick = parent.chopsticks[parent.NUMPHILS - 1];
    } else {
      this.leftStick = parent.chopsticks[position - 1];
    }

    // I'm hungry
    this.sated = false;
    philThread = new Thread(this);
  }

  public void run() {
    try {
      while (true) {
        Thread.sleep((int) (Math.random() * parent.grabDelay));
        setText("     ");
        rightStick.grab();
        setIcon(parent.imgs[parent.RIGHTSPOONDUKE]);

        Thread.sleep((int) (Math.random() * parent.grabDelay));
        leftStick.grab();
        setIcon(parent.imgs[parent.BOTHSPOONSDUKE]);

        Thread.sleep((int) (Math.random() * parent.grabDelay));
        rightStick.release();
        leftStick.release();
        setIcon(parent.imgs[parent.HUNGRYDUKE]);
        setText("Mmmm!");
        sated = true;

        Thread.sleep((int) (Math.random() * parent.grabDelay * 4));
        sated = false;
      }
    } catch (java.lang.InterruptedException e) {
    }
    leftStick.releaseIfMine();
    rightStick.releaseIfMine();
    setIcon(parent.imgs[parent.HUNGRYDUKE]);
    setText(parent.names[position]);
    sated = false;
    philThread = new Thread(this);
  }
}

class Chopstick {
  Thread holder = null;

  public synchronized void grab() throws InterruptedException {
    while (holder != null)
      wait();
    holder = Thread.currentThread();
  }

  public synchronized void release() {
    holder = null;
    notify();
  }

  public synchronized void releaseIfMine() {
    if (holder == Thread.currentThread())
      holder = null;
    notify();
  }
}