ComboBoxDemo2.java Source code

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Here is the source code for ComboBoxDemo2.java

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/* From http://java.sun.com/docs/books/tutorial/index.html */

/*
 * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * -Redistribution of source code must retain the above copyright notice, this
 *  list of conditions and the following disclaimer.
 *
 * -Redistribution in binary form must reproduce the above copyright notice,
 *  this list of conditions and the following disclaimer in the documentation
 *  and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility.
 */

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.SimpleDateFormat;
import java.util.Date;

import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

/* ComboBoxDemo2.java is a 1.4 application that requires no other files. */
public class ComboBoxDemo2 extends JPanel implements ActionListener {
    static JFrame frame;

    JLabel result;

    String currentPattern;

    public ComboBoxDemo2() {
        setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
        String[] patternExamples = { "dd MMMMM yyyy", "dd.MM.yy", "MM/dd/yy", "yyyy.MM.dd G 'at' hh:mm:ss z",
                "EEE, MMM d, ''yy", "h:mm a", "H:mm:ss:SSS", "K:mm a,z", "yyyy.MMMMM.dd GGG hh:mm aaa" };

        currentPattern = patternExamples[0];

        //Set up the UI for selecting a pattern.
        JLabel patternLabel1 = new JLabel("Enter the pattern string or");
        JLabel patternLabel2 = new JLabel("select one from the list:");

        JComboBox patternList = new JComboBox(patternExamples);
        patternList.setEditable(true);
        patternList.addActionListener(this);

        //Create the UI for displaying result.
        JLabel resultLabel = new JLabel("Current Date/Time", JLabel.LEADING); //==
        // LEFT
        result = new JLabel(" ");
        result.setForeground(Color.black);
        result.setBorder(BorderFactory.createCompoundBorder(BorderFactory.createLineBorder(Color.black),
                BorderFactory.createEmptyBorder(5, 5, 5, 5)));

        //Lay out everything.
        JPanel patternPanel = new JPanel();
        patternPanel.setLayout(new BoxLayout(patternPanel, BoxLayout.PAGE_AXIS));
        patternPanel.add(patternLabel1);
        patternPanel.add(patternLabel2);
        patternList.setAlignmentX(Component.LEFT_ALIGNMENT);
        patternPanel.add(patternList);

        JPanel resultPanel = new JPanel(new GridLayout(0, 1));
        resultPanel.add(resultLabel);
        resultPanel.add(result);

        patternPanel.setAlignmentX(Component.LEFT_ALIGNMENT);
        resultPanel.setAlignmentX(Component.LEFT_ALIGNMENT);

        add(patternPanel);
        add(Box.createRigidArea(new Dimension(0, 10)));
        add(resultPanel);

        setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));

        reformat();
    } //constructor

    public void actionPerformed(ActionEvent e) {
        JComboBox cb = (JComboBox) e.getSource();
        String newSelection = (String) cb.getSelectedItem();
        currentPattern = newSelection;
        reformat();
    }

    /** Formats and displays today's date. */
    public void reformat() {
        Date today = new Date();
        SimpleDateFormat formatter = new SimpleDateFormat(currentPattern);
        try {
            String dateString = formatter.format(today);
            result.setForeground(Color.black);
            result.setText(dateString);
        } catch (IllegalArgumentException iae) {
            result.setForeground(Color.red);
            result.setText("Error: " + iae.getMessage());
        }
    }

    /**
     * Create the GUI and show it. For thread safety, this method should be
     * invoked from the event-dispatching thread.
     */
    private static void createAndShowGUI() {
        //Make sure we have nice window decorations.
        JFrame.setDefaultLookAndFeelDecorated(true);

        //Create and set up the window.
        JFrame frame = new JFrame("ComboBoxDemo2");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        JComponent newContentPane = new ComboBoxDemo2();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}