src/demo/share/jfc/Metalworks/MetalworksHelp.java

/*
 * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions 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 Oracle nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * This source code is provided to illustrate the usage of a given feature
 * or technique and has been deliberately simplified. Additional steps
 * required for a production-quality application, such as security checks,
 * input validation and proper error handling, might not be present in
 * this sample code.
 */



import javax.swing.*;
import java.awt.*;
import java.net.URL;
import java.net.MalformedURLException;
import java.io.*;
import javax.swing.text.*;
import javax.swing.event.*;


/**
 * @author Steve Wilson
 * @author Alexander Kouznetsov
 */
@SuppressWarnings("serial")
public class MetalworksHelp extends JInternalFrame {

    public MetalworksHelp() {
        super("Help", true, true, true, true);

        setFrameIcon((Icon) UIManager.get("Tree.openIcon")); // PENDING(steve) need more general place to get this icon
        setBounds(200, 25, 400, 400);
        HtmlPane html = new HtmlPane();
        setContentPane(html);
    }
}


@SuppressWarnings("serial")
class HtmlPane extends JScrollPane implements HyperlinkListener {

    JEditorPane html;

    @SuppressWarnings("LeakingThisInConstructor")
    public HtmlPane() {
        try {
            URL url = getClass().getResource("/resources/HelpFiles/toc.html");
            html = new JEditorPane(url);
            html.setEditable(false);
            html.addHyperlinkListener(this);
            html.putClientProperty(JEditorPane.HONOR_DISPLAY_PROPERTIES,
                    Boolean.TRUE);
            JViewport vp = getViewport();
            vp.add(html);
        } catch (MalformedURLException e) {
            System.out.println("Malformed URL: " + e);
        } catch (IOException e) {
            System.out.println("IOException: " + e);
        }
    }

    /**
     * Notification of a change relative to a
     * hyperlink.
     */
    public void hyperlinkUpdate(HyperlinkEvent e) {
        if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
            linkActivated(e.getURL());
        }
    }

    /**
     * Follows the reference in an
     * link.  The given url is the requested reference.
     * By default this calls <a href="#setPage">setPage</a>,
     * and if an exception is thrown the original previous
     * document is restored and a beep sounded.  If an
     * attempt was made to follow a link, but it represented
     * a malformed url, this method will be called with a
     * null argument.
     *
     * @param u the URL to follow
     */
    protected void linkActivated(URL u) {
        Cursor c = html.getCursor();
        Cursor waitCursor = Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR);
        html.setCursor(waitCursor);
        SwingUtilities.invokeLater(new PageLoader(u, c));
    }


    /**
     * temporary class that loads synchronously (although
     * later than the request so that a cursor change
     * can be done).
     */
    class PageLoader implements Runnable {

        PageLoader(URL u, Cursor c) {
            url = u;
            cursor = c;
        }

        public void run() {
            if (url == null) {
                // restore the original cursor
                html.setCursor(cursor);

                // PENDING(prinz) remove this hack when
                // automatic validation is activated.
                Container parent = html.getParent();
                parent.repaint();
            } else {
                Document doc = html.getDocument();
                try {
                    html.setPage(url);
                } catch (IOException ioe) {
                    html.setDocument(doc);
                    getToolkit().beep();
                } finally {
                    // schedule the cursor to revert after
                    // the paint has happended.
                    url = null;
                    SwingUtilities.invokeLater(this);
                }
            }
        }
        URL url;
        Cursor cursor;
    }
}