Java AbstractSpinnerModel .fireStateChanged ()

protected void fireStateChanged()

/*// www .  j a  v a  2s .c om
 This program is a part of the companion code for Core Java 8th ed.
 (http://horstmann.com/corejava)

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.awt.BorderLayout;
import java.awt.GraphicsEnvironment;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.DateFormat;
import java.text.SimpleDateFormat;

import javax.swing.AbstractSpinnerModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSpinner;
import javax.swing.SpinnerDateModel;
import javax.swing.SpinnerListModel;
import javax.swing.SpinnerNumberModel;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

/**
 * A program to test spinners.
 * 
 * @version 1.02 2007-08-01
 * @author Cay Horstmann
 */

public class Main extends JFrame {
  public static void main(String[] args) {
    Main frame = new Main();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
  }

  public Main() {
    setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
    JPanel buttonPanel = new JPanel();
    okButton = new JButton("Ok");
    buttonPanel.add(okButton);
    add(buttonPanel, BorderLayout.SOUTH);

    mainPanel = new JPanel();
    mainPanel.setLayout(new GridLayout(0, 3));
    add(mainPanel, BorderLayout.CENTER);

    JSpinner defaultSpinner = new JSpinner();
    addRow("Default", defaultSpinner);

    JSpinner boundedSpinner = new JSpinner(
        new SpinnerNumberModel(5, 0, 10, 0.5));
    addRow("Bounded", boundedSpinner);

    String[] fonts = GraphicsEnvironment.getLocalGraphicsEnvironment()
        .getAvailableFontFamilyNames();

    JSpinner listSpinner = new JSpinner(new SpinnerListModel(fonts));
    addRow("List", listSpinner);

    JSpinner reverseListSpinner = new JSpinner(new SpinnerListModel(fonts) {
      public Object getNextValue() {
        return super.getPreviousValue();
      }

      public Object getPreviousValue() {
        return super.getNextValue();
      }
    });
    addRow("Reverse List", reverseListSpinner);

    JSpinner dateSpinner = new JSpinner(new SpinnerDateModel());
    addRow("Date", dateSpinner);

    JSpinner betterDateSpinner = new JSpinner(new SpinnerDateModel());
    String pattern = ((SimpleDateFormat) DateFormat.getDateInstance())
        .toPattern();
    betterDateSpinner.setEditor(new JSpinner.DateEditor(betterDateSpinner,
        pattern));
    addRow("Better Date", betterDateSpinner);

    JSpinner timeSpinner = new JSpinner(new SpinnerDateModel());
    pattern = ((SimpleDateFormat) DateFormat.getTimeInstance(DateFormat.SHORT))
        .toPattern();
    timeSpinner.setEditor(new JSpinner.DateEditor(timeSpinner, pattern));
    addRow("Time", timeSpinner);

    JSpinner permSpinner = new JSpinner(new PermutationSpinnerModel("meat"));
    addRow("Word permutations", permSpinner);
  }

  /**
   * Adds a row to the main panel.
   * 
   * @param labelText
   *          the label of the spinner
   * @param spinner
   *          the sample spinner
   */
  public void addRow(String labelText, final JSpinner spinner) {
    mainPanel.add(new JLabel(labelText));
    mainPanel.add(spinner);
    final JLabel valueLabel = new JLabel();
    mainPanel.add(valueLabel);
    okButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent event) {
        Object value = spinner.getValue();
        valueLabel.setText(value.toString());
      }
    });
  }

  public static final int DEFAULT_WIDTH = 400;
  public static final int DEFAULT_HEIGHT = 250;

  private JPanel mainPanel;
  private JButton okButton;
}

/**
 * A model that dynamically generates word permutations
 */
class PermutationSpinnerModel extends AbstractSpinnerModel {
  /**
   * Constructs the model.
   * 
   * @param w
   *          the word to permute
   */
  public PermutationSpinnerModel(String w) {
    word = w;
    ChangeListener lis = new ChangeListener(){
      @Override
      public void stateChanged(ChangeEvent e) {
        System.out.println(e);
      }      
    };
    addChangeListener(lis);
    ChangeListener[] listeners = getListeners(ChangeListener.class);
    removeChangeListener(lis);
  }

  public Object getValue() {
    return word;
  }

  public void setValue(Object value) {
    if (!(value instanceof String))
      throw new IllegalArgumentException();
    word = (String) value;
    fireStateChanged();
  }

  public Object getNextValue() {
    int[] codePoints = toCodePointArray(word);
    for (int i = codePoints.length - 1; i > 0; i--) {
      if (codePoints[i - 1] < codePoints[i]) {
        int j = codePoints.length - 1;
        while (codePoints[i - 1] > codePoints[j])
          j--;
        swap(codePoints, i - 1, j);
        reverse(codePoints, i, codePoints.length - 1);
        return new String(codePoints, 0, codePoints.length);
      }
    }
    reverse(codePoints, 0, codePoints.length - 1);
    return new String(codePoints, 0, codePoints.length);
  }

  public Object getPreviousValue() {
    int[] codePoints = toCodePointArray(word);
    for (int i = codePoints.length - 1; i > 0; i--) {
      if (codePoints[i - 1] > codePoints[i]) {
        int j = codePoints.length - 1;
        while (codePoints[i - 1] < codePoints[j])
          j--;
        swap(codePoints, i - 1, j);
        reverse(codePoints, i, codePoints.length - 1);
        return new String(codePoints, 0, codePoints.length);
      }
    }
    reverse(codePoints, 0, codePoints.length - 1);
    return new String(codePoints, 0, codePoints.length);
  }

  private static int[] toCodePointArray(String str) {
    int[] codePoints = new int[str.codePointCount(0, str.length())];
    for (int i = 0, j = 0; i < str.length(); i++, j++) {
      int cp = str.codePointAt(i);
      if (Character.isSupplementaryCodePoint(cp))
        i++;
      codePoints[j] = cp;
    }
    return codePoints;
  }

  private static void swap(int[] a, int i, int j) {
    int temp = a[i];
    a[i] = a[j];
    a[j] = temp;
  }

  private static void reverse(int[] a, int i, int j) {
    while (i < j) {
      swap(a, i, j);
      i++;
      j--;
    }
  }

  private String word;
}