I have a program for which I am designing a help menu. The program allows you to add squares, ovals, and other shapes, and move them, rotate them, etc. I'm setting up some HTML pages that explain how to do different tasks. So when the user pulls down the help menu, I'd like something like this to display in a JFrame:

How do you add a shape?
How do you move a shape?
How do you rotate a shape?

The links above don't lead anywhere from Daniweb, but if you hover over them, you'll notice that they will link to HTML files on the local machine. I'd like the user to be able to click on them, then when they are clicked, a browser opens up with the appropriate help page. At this point, help should be separate from the Java program. The Java program should provide the initial options, then when one is chosen, the browser takes over and is independent of the program.

Currently my first attempt is to use a JEditorPane. Click a button and either Yahoo or Google comes up. I'd like to have a browser come up instead of using the JEditorPane. Second, I'd like to use links like above rather than JButtons as I currently have it, but I don't know how to make text clickable. Can anyone steer me in the right direction? Thanks.

import java.awt.*;
import java.awt.event.*;
import java.io.IOException;
import javax.swing.*;
import javax.swing.event.*;



public class HelpMain extends JFrame implements ActionListener, HyperlinkListener
{
    JPanel panel1;
    JPanel panel2;
    JEditorPane pane;
    JButton googleButton;
    JButton yahooButton;
 
    
    public static void main (String args[])
    {
        new HelpMain ();
    }
  
    
    public HelpMain ()
    {
        panel1 = new JPanel ();
        panel2 = new JPanel ();
        LayoutManager lm = new GridLayout (2,1);
        setLayout(lm);
        panel1.setBackground(Color.GREEN);
        googleButton = new JButton ("Google");
        yahooButton = new JButton ("Yahoo");
        googleButton.addActionListener(this);
        yahooButton.addActionListener (this);
        panel1.add (googleButton);
        panel1.add (yahooButton);
        panel2.setBackground(Color.CYAN);
        pane = new JEditorPane ();
        pane.setEditable(false);
        pane.addHyperlinkListener(this);
        panel2.add (pane);
        add (panel1);
        add (panel2);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(1000, 600);
        setVisible(true);        
    }

    public void actionPerformed(ActionEvent e)
    {
        if (e.getSource () == googleButton)
        {
            setHTMLPage ("http://www.google.com");
        }
        else if (e.getSource () == yahooButton)
        {
            setHTMLPage ("http://www.yahoo.com");
        }
    }
    
    public void setHTMLPage (String page)
    {
        try
        {
            pane.setPage(page);
        }
        catch (IOException ex)
        {
            System.out.println ("Problem setting page.");
        }
    }

    public void hyperlinkUpdate(HyperlinkEvent he)
    {
        System.out.println ("In Hyperlink Listener");
        if (he.getEventType() == HyperlinkEvent.EventType.ACTIVATED) 
        {
            try 
            {
                pane.setPage(he.getURL());
            }
            catch(Exception ex) 
            {
                System.out.println ("Problem following link.");
            }
        }
    }
}

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For launching the default browser, we use a small utility class called BrowserLauncher that one of the guys here found a few years back in a JavaWorld posting. I've pasted that into your example code as a static class (just for convenience - it should be a public class of its own) and altered your lower JEditorPane to display a hyperlink that opens Google in the default browser.

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

import java.io.File;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class HelpMain extends JFrame implements ActionListener, HyperlinkListener
{
    JPanel panel1;
    JPanel panel2;
    JEditorPane pane;
    JButton googleButton;
    JButton yahooButton;
 
    
    public static void main (String args[])
    {
        new HelpMain();
    }
  
    
    public HelpMain()
    {
        panel1 = new JPanel ();
        panel2 = new JPanel ();
        LayoutManager lm = new GridLayout (2,1);
        setLayout(lm);
        panel1.setBackground(Color.GREEN);
        googleButton = new JButton ("Google");
        yahooButton = new JButton ("Yahoo");
        googleButton.addActionListener(this);
        yahooButton.addActionListener (this);
        panel1.add (googleButton);
        panel1.add (yahooButton);
        panel2.setBackground(Color.CYAN);
        pane = new JEditorPane ();
        pane.setEditable(false);
        pane.addHyperlinkListener(this);
        
        // Added this part
        pane.setContentType("text/html");
        pane.setText("<A href='http://www.google.com'>Google</A>");
        
        panel2.add (pane);
        add (panel1);
        add (panel2);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(1000, 600);
        setVisible(true);        
    }

    public void actionPerformed(ActionEvent e)
    {
        if (e.getSource () == googleButton)
        {
            setHTMLPage ("http://www.google.com");
        }
        else if (e.getSource () == yahooButton)
        {
            setHTMLPage ("http://www.yahoo.com");
        }
    }
    
    public void setHTMLPage (String page)
    {
        try
        {
            pane.setPage(page);
        }
        catch (IOException ex)
        {
            System.out.println ("Problem setting page.");
        }
    }

    public void hyperlinkUpdate(HyperlinkEvent he)
    {
        System.out.println ("In Hyperlink Listener");
        if (he.getEventType() == HyperlinkEvent.EventType.ACTIVATED) 
        {
            try 
            {
                // Changed this to use the launcher
                BrowserLauncher.openURL(he.getURL().toString());
            }
            catch(Exception ex) 
            {
                System.out.println ("Problem following link.");
            }
        }
    }
    




/**
 * BrowserLauncher is a class that provides one static method, openURL, which opens the default
 * web browser for the current user of the system to the given URL.  It may support other
 * protocols depending on the system -- mailto, ftp, etc. -- but that has not been rigorously
 * tested and is not guaranteed to work.
 * <p>
 * Yes, this is platform-specific code, and yes, it may rely on classes on certain platforms
 * that are not part of the standard JDK.  What we're trying to do, though, is to take something
 * that's frequently desirable but inherently platform-specific -- opening a default browser --
 * and allow programmers (you, for example) to do so without worrying about dropping into native
 * code or doing anything else similarly evil.
 * <p>
 * Anyway, this code is completely in Java and will run on all JDK 1.1-compliant systems without
 * modification or a need for additional libraries.  All classes that are required on certain
 * platforms to allow this to run are dynamically loaded at runtime via reflection and, if not
 * found, will not cause this to do anything other than returning an error when opening the
 * browser.
 * <p>
 * There are certain system requirements for this class, as it's running through Runtime.exec(),
 * which is Java's way of making a native system call.  Currently, this requires that a Macintosh
 * have a Finder which supports the GURL event, which is true for Mac OS 8.0 and 8.1 systems that
 * have the Internet Scripting AppleScript dictionary installed in the Scripting Additions folder
 * in the Extensions folder (which is installed by default as far as I know under Mac OS 8.0 and
 * 8.1), and for all Mac OS 8.5 and later systems.  On Windows, it only runs under Win32 systems
 * (Windows 95, 98, and NT 4.0, as well as later versions of all).  On other systems, this drops
 * back from the inherently platform-sensitive concept of a default browser and simply attempts
 * to launch Netscape via a shell command.
 * <p>
 * This code is Copyright 1999-2001 by Eric Albert (ejalbert@cs.stanford.edu) and may be
 * redistributed or modified in any form without restrictions as long as the portion of this
 * comment from this paragraph through the end of the comment is not removed.  The author
 * requests that he be notified of any application, applet, or other binary that makes use of
 * this code, but that's more out of curiosity than anything and is not required.  This software
 * includes no warranty.  The author is not repsonsible for any loss of data or functionality
 * or any adverse or unexpected effects of using this software.
 * <p>
 * Credits:
 * <br>Steven Spencer, JavaWorld magazine (<a href="http://www.javaworld.com/javaworld/javatips/jw-javatip66.html">Java Tip 66</a>)
 * <br>Thanks also to Ron B. Yeh, Eric Shapiro, Ben Engber, Paul Teitlebaum, Andrea Cantatore,
 * Larry Barowski, Trevor Bedzek, Frank Miedrich, and Ron Rabakukk
 *
 * @author Eric Albert (<a href="mailto:ejalbert@cs.stanford.edu">ejalbert@cs.stanford.edu</a>)
 * @version 1.4b1 (Released June 20, 2001)
 */
static class BrowserLauncher {

	/**
	 * The Java virtual machine that we are running on.  Actually, in most cases we only care
	 * about the operating system, but some operating systems require us to switch on the VM. */
	private static int jvm;

	/** The browser for the system */
	private static Object browser;

	/**
	 * Caches whether any classes, methods, and fields that are not part of the JDK and need to
	 * be dynamically loaded at runtime loaded successfully.
	 * <p>
	 * Note that if this is <code>false</code>, <code>openURL()</code> will always return an
	 * IOException.
	 */
	private static boolean loadedWithoutErrors;

	/** The com.apple.mrj.MRJFileUtils class */
	private static Class mrjFileUtilsClass;

	/** The com.apple.mrj.MRJOSType class */
	private static Class mrjOSTypeClass;

	/** The com.apple.MacOS.AEDesc class */
	private static Class aeDescClass;
	
	/** The <init>(int) method of com.apple.MacOS.AETarget */
	private static Constructor aeTargetConstructor;
	
	/** The <init>(int, int, int) method of com.apple.MacOS.AppleEvent */
	private static Constructor appleEventConstructor;
	
	/** The <init>(String) method of com.apple.MacOS.AEDesc */
	private static Constructor aeDescConstructor;
	
	/** The findFolder method of com.apple.mrj.MRJFileUtils */
	private static Method findFolder;

	/** The getFileCreator method of com.apple.mrj.MRJFileUtils */
	private static Method getFileCreator;
	
	/** The getFileType method of com.apple.mrj.MRJFileUtils */
	private static Method getFileType;
	
	/** The openURL method of com.apple.mrj.MRJFileUtils */
	private static Method openURL;
	
	/** The makeOSType method of com.apple.MacOS.OSUtils */
	private static Method makeOSType;
	
	/** The putParameter method of com.apple.MacOS.AppleEvent */
	private static Method putParameter;
	
	/** The sendNoReply method of com.apple.MacOS.AppleEvent */
	private static Method sendNoReply;
	
	/** Actually an MRJOSType pointing to the System Folder on a Macintosh */
	private static Object kSystemFolderType;

	/** The keyDirectObject AppleEvent parameter type */
	private static Integer keyDirectObject;

	/** The kAutoGenerateReturnID AppleEvent code */
	private static Integer kAutoGenerateReturnID;
	
	/** The kAnyTransactionID AppleEvent code */
	private static Integer kAnyTransactionID;

	/** The linkage object required for JDirect 3 on Mac OS X. */
	private static Object linkage;
	
	/** The framework to reference on Mac OS X */
	private static final String JDirect_MacOSX = "/System/Library/Frameworks/Carbon.framework/Frameworks/HIToolbox.framework/HIToolbox";

	/** JVM constant for MRJ 2.0 */
	private static final int MRJ_2_0 = 0;
	
	/** JVM constant for MRJ 2.1 or later */
	private static final int MRJ_2_1 = 1;

	/** JVM constant for Java on Mac OS X 10.0 (MRJ 3.0) */
	private static final int MRJ_3_0 = 3;
	
	/** JVM constant for MRJ 3.1 */
	private static final int MRJ_3_1 = 4;

	/** JVM constant for any Windows NT JVM */
	private static final int WINDOWS_NT = 5;
	
	/** JVM constant for any Windows 9x JVM */
	private static final int WINDOWS_9x = 6;

	/** JVM constant for any other platform */
	private static final int OTHER = -1;

	/**
	 * The file type of the Finder on a Macintosh.  Hardcoding "Finder" would keep non-U.S. English
	 * systems from working properly.
	 */
	private static final String FINDER_TYPE = "FNDR";

	/**
	 * The creator code of the Finder on a Macintosh, which is needed to send AppleEvents to the
	 * application.
	 */
	private static final String FINDER_CREATOR = "MACS";

	/** The name for the AppleEvent type corresponding to a GetURL event. */
	private static final String GURL_EVENT = "GURL";

	/**
	 * The first parameter that needs to be passed into Runtime.exec() to open the default web
	 * browser on Windows.
	 */
    private static final String FIRST_WINDOWS_PARAMETER = "/c";
    
    /** The second parameter for Runtime.exec() on Windows. */
    private static final String SECOND_WINDOWS_PARAMETER = "start";
    
    /**
     * The third parameter for Runtime.exec() on Windows.  This is a "title"
     * parameter that the command line expects.  Setting this parameter allows
     * URLs containing spaces to work.
     */
    private static final String THIRD_WINDOWS_PARAMETER = "\"\"";
	
	/**
	 * The shell parameters for Netscape that opens a given URL in an already-open copy of Netscape
	 * on many command-line systems.
	 */
	private static final String NETSCAPE_REMOTE_PARAMETER = "-remote";
	private static final String NETSCAPE_OPEN_PARAMETER_START = "'openURL(";
	private static final String NETSCAPE_OPEN_PARAMETER_END = ")'";
	
	/**
	 * The message from any exception thrown throughout the initialization process.
	 */
	private static String errorMessage;

	/**
	 * An initialization block that determines the operating system and loads the necessary
	 * runtime data.
	 */
	static {
		loadedWithoutErrors = true;
		String osName = System.getProperty("os.name");
		if (osName.startsWith("Mac OS")) {
			String mrjVersion = System.getProperty("mrj.version");
			String majorMRJVersion = mrjVersion.substring(0, 3);
			try {
				double version = Double.valueOf(majorMRJVersion).doubleValue();
				if (version == 2) {
					jvm = MRJ_2_0;
				} else if (version >= 2.1 && version < 3) {
					// Assume that all 2.x versions of MRJ work the same.  MRJ 2.1 actually
					// works via Runtime.exec() and 2.2 supports that but has an openURL() method
					// as well that we currently ignore.
					jvm = MRJ_2_1;
				} else if (version == 3.0) {
					jvm = MRJ_3_0;
				} else if (version >= 3.1) {
					// Assume that all 3.1 and later versions of MRJ work the same.
					jvm = MRJ_3_1;
				} else {
					loadedWithoutErrors = false;
					errorMessage = "Unsupported MRJ version: " + version;
				}
			} catch (NumberFormatException nfe) {
				loadedWithoutErrors = false;
				errorMessage = "Invalid MRJ version: " + mrjVersion;
			}
		} else if (osName.startsWith("Windows")) {
			if (osName.indexOf("9") != -1) {
				jvm = WINDOWS_9x;
			} else {
				jvm = WINDOWS_NT;
			}
		} else {
			jvm = OTHER;
		}
		
		if (loadedWithoutErrors) {	// if we haven't hit any errors yet
			loadedWithoutErrors = loadClasses();
		}
	}

	/**
	 * This class should be never be instantiated; this just ensures so.
	 */
	private BrowserLauncher() { }
	
	/**
	 * Called by a static initializer to load any classes, fields, and methods required at runtime
	 * to locate the user's web browser.
	 * @return <code>true</code> if all intialization succeeded
	 *			<code>false</code> if any portion of the initialization failed
	 */
	private static boolean loadClasses() {
		switch (jvm) {
			case MRJ_2_0:
				try {
					Class aeTargetClass = Class.forName("com.apple.MacOS.AETarget");
					Class osUtilsClass = Class.forName("com.apple.MacOS.OSUtils");
					Class appleEventClass = Class.forName("com.apple.MacOS.AppleEvent");
					Class aeClass = Class.forName("com.apple.MacOS.ae");
					aeDescClass = Class.forName("com.apple.MacOS.AEDesc");

					aeTargetConstructor = aeTargetClass.getDeclaredConstructor(new Class [] { int.class });
					appleEventConstructor = appleEventClass.getDeclaredConstructor(new Class[] { int.class, int.class, aeTargetClass, int.class, int.class });
					aeDescConstructor = aeDescClass.getDeclaredConstructor(new Class[] { String.class });

					makeOSType = osUtilsClass.getDeclaredMethod("makeOSType", new Class [] { String.class });
					putParameter = appleEventClass.getDeclaredMethod("putParameter", new Class[] { int.class, aeDescClass });
					sendNoReply = appleEventClass.getDeclaredMethod("sendNoReply", new Class[] { });

					Field keyDirectObjectField = aeClass.getDeclaredField("keyDirectObject");
					keyDirectObject = (Integer) keyDirectObjectField.get(null);
					Field autoGenerateReturnIDField = appleEventClass.getDeclaredField("kAutoGenerateReturnID");
					kAutoGenerateReturnID = (Integer) autoGenerateReturnIDField.get(null);
					Field anyTransactionIDField = appleEventClass.getDeclaredField("kAnyTransactionID");
					kAnyTransactionID = (Integer) anyTransactionIDField.get(null);
				} catch (ClassNotFoundException cnfe) {
					errorMessage = cnfe.getMessage();
					return false;
				} catch (NoSuchMethodException nsme) {
					errorMessage = nsme.getMessage();
					return false;
				} catch (NoSuchFieldException nsfe) {
					errorMessage = nsfe.getMessage();
					return false;
				} catch (IllegalAccessException iae) {
					errorMessage = iae.getMessage();
					return false;
				}
				break;
			case MRJ_2_1:
				try {
					mrjFileUtilsClass = Class.forName("com.apple.mrj.MRJFileUtils");
					mrjOSTypeClass = Class.forName("com.apple.mrj.MRJOSType");
					Field systemFolderField = mrjFileUtilsClass.getDeclaredField("kSystemFolderType");
					kSystemFolderType = systemFolderField.get(null);
					findFolder = mrjFileUtilsClass.getDeclaredMethod("findFolder", new Class[] { mrjOSTypeClass });
					getFileCreator = mrjFileUtilsClass.getDeclaredMethod("getFileCreator", new Class[] { File.class });
					getFileType = mrjFileUtilsClass.getDeclaredMethod("getFileType", new Class[] { File.class });
				} catch (ClassNotFoundException cnfe) {
					errorMessage = cnfe.getMessage();
					return false;
				} catch (NoSuchFieldException nsfe) {
					errorMessage = nsfe.getMessage();
					return false;
				} catch (NoSuchMethodException nsme) {
					errorMessage = nsme.getMessage();
					return false;
				} catch (SecurityException se) {
					errorMessage = se.getMessage();
					return false;
				} catch (IllegalAccessException iae) {
					errorMessage = iae.getMessage();
					return false;
				}
				break;
			case MRJ_3_0:
			    try {
					Class linker = Class.forName("com.apple.mrj.jdirect.Linker");
					Constructor constructor = linker.getConstructor(new Class[]{ Class.class });
					linkage = constructor.newInstance(new Object[] { BrowserLauncher.class });
				} catch (ClassNotFoundException cnfe) {
					errorMessage = cnfe.getMessage();
					return false;
				} catch (NoSuchMethodException nsme) {
					errorMessage = nsme.getMessage();
					return false;
				} catch (InvocationTargetException ite) {
					errorMessage = ite.getMessage();
					return false;
				} catch (InstantiationException ie) {
					errorMessage = ie.getMessage();
					return false;
				} catch (IllegalAccessException iae) {
					errorMessage = iae.getMessage();
					return false;
				}
				break;
			case MRJ_3_1:
				try {
					mrjFileUtilsClass = Class.forName("com.apple.mrj.MRJFileUtils");
					openURL = mrjFileUtilsClass.getDeclaredMethod("openURL", new Class[] { String.class });
				} catch (ClassNotFoundException cnfe) {
					errorMessage = cnfe.getMessage();
					return false;
				} catch (NoSuchMethodException nsme) {
					errorMessage = nsme.getMessage();
					return false;
				}
				break;
			default:
			    break;
		}
		return true;
	}

	/**
	 * Attempts to locate the default web browser on the local system.  Caches results so it
	 * only locates the browser once for each use of this class per JVM instance.
	 * @return The browser for the system.  Note that this may not be what you would consider
	 *			to be a standard web browser; instead, it's the application that gets called to
	 *			open the default web browser.  In some cases, this will be a non-String object
	 *			that provides the means of calling the default browser.
	 */
	private static Object locateBrowser() {
		if (browser != null) {
			return browser;
		}
		switch (jvm) {
			case MRJ_2_0:
				try {
					Integer finderCreatorCode = (Integer) makeOSType.invoke(null, new Object[] { FINDER_CREATOR });
					Object aeTarget = aeTargetConstructor.newInstance(new Object[] { finderCreatorCode });
					Integer gurlType = (Integer) makeOSType.invoke(null, new Object[] { GURL_EVENT });
					Object appleEvent = appleEventConstructor.newInstance(new Object[] { gurlType, gurlType, aeTarget, kAutoGenerateReturnID, kAnyTransactionID });
					// Don't set browser = appleEvent because then the next time we call
					// locateBrowser(), we'll get the same AppleEvent, to which we'll already have
					// added the relevant parameter. Instead, regenerate the AppleEvent every time.
					// There's probably a way to do this better; if any has any ideas, please let
					// me know.
					return appleEvent;
				} catch (IllegalAccessException iae) {
					browser = null;
					errorMessage = iae.getMessage();
					return browser;
				} catch (InstantiationException ie) {
					browser = null;
					errorMessage = ie.getMessage();
					return browser;
				} catch (InvocationTargetException ite) {
					browser = null;
					errorMessage = ite.getMessage();
					return browser;
				}
			case MRJ_2_1:
				File systemFolder;
				try {
					systemFolder = (File) findFolder.invoke(null, new Object[] { kSystemFolderType });
				} catch (IllegalArgumentException iare) {
					browser = null;
					errorMessage = iare.getMessage();
					return browser;
				} catch (IllegalAccessException iae) {
					browser = null;
					errorMessage = iae.getMessage();
					return browser;
				} catch (InvocationTargetException ite) {
					browser = null;
					errorMessage = ite.getTargetException().getClass() + ": " + ite.getTargetException().getMessage();
					return browser;
				}
				String[] systemFolderFiles = systemFolder.list();
				// Avoid a FilenameFilter because that can't be stopped mid-list
				for(int i = 0; i < systemFolderFiles.length; i++) {
					try {
						File file = new File(systemFolder, systemFolderFiles[i]);
						if (!file.isFile()) {
							continue;
						}
						// We're looking for a file with a creator code of 'MACS' and
						// a type of 'FNDR'.  Only requiring the type results in non-Finder
						// applications being picked up on certain Mac OS 9 systems,
						// especially German ones, and sending a GURL event to those
						// applications results in a logout under Multiple Users.
						Object fileType = getFileType.invoke(null, new Object[] { file });
						if (FINDER_TYPE.equals(fileType.toString())) {
							Object fileCreator = getFileCreator.invoke(null, new Object[] { file });
							if (FINDER_CREATOR.equals(fileCreator.toString())) {
								browser = file.toString();	// Actually the Finder, but that's OK
								return browser;
							}
						}
					} catch (IllegalArgumentException iare) {
						browser = browser;
						errorMessage = iare.getMessage();
						return null;
					} catch (IllegalAccessException iae) {
						browser = null;
						errorMessage = iae.getMessage();
						return browser;
					} catch (InvocationTargetException ite) {
						browser = null;
						errorMessage = ite.getTargetException().getClass() + ": " + ite.getTargetException().getMessage();
						return browser;
					}
				}
				browser = null;
				break;
			case MRJ_3_0:
			case MRJ_3_1:
				browser = "";	// Return something non-null
				break;
			case WINDOWS_NT:
				browser = "cmd.exe";
				break;
			case WINDOWS_9x:
				browser = "command.com";
				break;
			case OTHER:
			default:
				browser = "netscape";
				break;
		}
		return browser;
	}

	/**
	 * Attempts to open the default web browser to the given URL.
	 * @param url The URL to open
	 * @throws IOException If the web browser could not be located or does not run
	 */
	public static void openURL(String url) throws IOException {
		if (!loadedWithoutErrors) {
			throw new IOException("Exception in finding browser: " + errorMessage);
		}
		Object browser = locateBrowser();
		if (browser == null) {
			throw new IOException("Unable to locate browser: " + errorMessage);
		}
		
		switch (jvm) {
			case MRJ_2_0:
				Object aeDesc = null;
				try {
					aeDesc = aeDescConstructor.newInstance(new Object[] { url });
					putParameter.invoke(browser, new Object[] { keyDirectObject, aeDesc });
					sendNoReply.invoke(browser, new Object[] { });
				} catch (InvocationTargetException ite) {
					throw new IOException("InvocationTargetException while creating AEDesc: " + ite.getMessage());
				} catch (IllegalAccessException iae) {
					throw new IOException("IllegalAccessException while building AppleEvent: " + iae.getMessage());
				} catch (InstantiationException ie) {
					throw new IOException("InstantiationException while creating AEDesc: " + ie.getMessage());
				} finally {
					aeDesc = null;	// Encourage it to get disposed if it was created
					browser = null;	// Ditto
				}
				break;
			case MRJ_2_1:
				Runtime.getRuntime().exec(new String[] { (String) browser, url } );
				break;
			case MRJ_3_0:
				int[] instance = new int[1];
				int result = ICStart(instance, 0);
				if (result == 0) {
					int[] selectionStart = new int[] { 0 };
					byte[] urlBytes = url.getBytes();
					int[] selectionEnd = new int[] { urlBytes.length };
					result = ICLaunchURL(instance[0], new byte[] { 0 }, urlBytes,
											urlBytes.length, selectionStart,
											selectionEnd);
					if (result == 0) {
						// Ignore the return value; the URL was launched successfully
						// regardless of what happens here.
						ICStop(instance);
					} else {
						throw new IOException("Unable to launch URL: " + result);
					}
				} else {
					throw new IOException("Unable to create an Internet Config instance: " + result);
				}
				break;
			case MRJ_3_1:
				try {
					openURL.invoke(null, new Object[] { url });
				} catch (InvocationTargetException ite) {
					throw new IOException("InvocationTargetException while calling openURL: " + ite.getMessage());
				} catch (IllegalAccessException iae) {
					throw new IOException("IllegalAccessException while calling openURL: " + iae.getMessage());
				}
				break;
		    case WINDOWS_NT:
		    case WINDOWS_9x:
		    	// Add quotes around the URL to allow ampersands and other special
		    	// characters to work.
				Process process = Runtime.getRuntime().exec(new String[] { (String) browser,
																FIRST_WINDOWS_PARAMETER,
																SECOND_WINDOWS_PARAMETER,
																THIRD_WINDOWS_PARAMETER,
																'"' + url + '"' });
				// This avoids a memory leak on some versions of Java on Windows.
				// That's hinted at in <http://developer.java.sun.com/developer/qow/archive/68/>.
				try {
					process.waitFor();
					process.exitValue();
				} catch (InterruptedException ie) {
					throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
				}
				break;
			case OTHER:
				// Assume that we're on Unix and that Netscape is installed
				
				// First, attempt to open the URL in a currently running session of Netscape
				process = Runtime.getRuntime().exec(new String[] { (String) browser,
													NETSCAPE_REMOTE_PARAMETER,
													NETSCAPE_OPEN_PARAMETER_START +
													url +
													NETSCAPE_OPEN_PARAMETER_END });
				try {
					int exitCode = process.waitFor();
					if (exitCode != 0) {	// if Netscape was not open
						Runtime.getRuntime().exec(new String[] { (String) browser, url });
					}
				} catch (InterruptedException ie) {
					throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
				}
				break;
			default:
				// This should never occur, but if it does, we'll try the simplest thing possible
				Runtime.getRuntime().exec(new String[] { (String) browser, url });
				break;
		}
	}

	/**
	 * Methods required for Mac OS X.  The presence of native methods does not cause
	 * any problems on other platforms.
	 */
	private native static int ICStart(int[] instance, int signature);
	private native static int ICStop(int[] instance);
	private native static int ICLaunchURL(int instance, byte[] hint, byte[] data, int len,
											int[] selectionStart, int[] selectionEnd);
}
    
}

Actually, if you're using JDK 6, I guess they've added a class that would take care of the browser part for you: http://java.sun.com/javase/6/docs/api/java/awt/Desktop.html

(We're still stuck at SE5 here for a bit longer, so I'm not as familiar with all the additions that SE6 brought yet :( )

Awesome. Thank you. I have SE 6, but I don't know whether everyone running the program will have it, so I'll probably use what you posted in post 2.

It works fine when using a website for links. I'm going to try to use files on the local machine. It also works fine when using local files when you run .class files and put the HTML file in the right directory. But I'm trying to stick all of the HTML files in a jar file along with the .class files. The problem with this, at least as I have done it, is that the program is looking OUTSIDE or the jar file for the file to link to. I'd like it to look INSIDE the jar file for the file to link to since that's where the file is located. I don't know whether that is possible or not. Here's my updated code. This has the buttons in it rather than the JEditorPane (I'm not going to keep the buttons, but that's no longer the problem).

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class HelpMain extends JFrame implements ActionListener
{
    JPanel panel1;
    JPanel panel2;
    JEditorPane pane;
    JButton googleButton;
    JButton fileButton;
 
    
    public static void main (String args[])
    {
        new HelpMain();
    }
  
    
    public HelpMain()
    {
        panel1 = new JPanel ();
        panel2 = new JPanel ();
        LayoutManager lm = new GridLayout (2,1);
        setLayout(lm);
        panel1.setBackground(Color.GREEN);
        googleButton = new JButton ("Google");
        fileButton = new JButton ("File");
        googleButton.addActionListener(this);
        fileButton.addActionListener (this);
        panel1.add (googleButton);
        panel1.add (fileButton);
        panel2.setBackground(Color.CYAN);

        add (panel1);
        add (panel2);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(1000, 600);
        setVisible(true);        
    }

    public void actionPerformed(ActionEvent e)
    {
        if (e.getSource () == googleButton)
        {
            setHTMLPage ("http://www.google.com");
        }
        else if (e.getSource () == fileButton)
        {
            setHTMLPage ("index.html");
        }
    }
    
    public void setHTMLPage (String page)
    {
        try
        {
              BrowserLauncher.openURL(page);
        }
        catch (IOException ex)
        {
            System.out.println ("Problem setting page.");
        }
    }

    // BrowserLauncher code.
}

In line 56, there is a file called "index.html" INSIDE the jar file that I am trying to open. The program is currently looking OUTSIDE the jar file in the directory where the jar file resides (i.e. "My Documents").

I'm not certain if the browser will open an html file in a jar. You can use getClass().getResource() to obtain a URL for a resource in a jar, but whether the browser will open it may be another story. Firefox doesn't seem to want to.

I'm not certain if the browser will open an html file in a jar. You can use getClass().getResource() to obtain a URL for a resource in a jar, but whether the browser will open it may be another story. Firefox doesn't seem to want to.

O.K., so is it generally the procedure to have a folder with help files outside of the jar file? It must come up a lot. I was thinking of creating a folder with all of the help files, then zipping that folder along with the jar into a zip file. The user could then download the zip file, unzip it, and problem solved. It's one extra step for the user, but only one, so not that big of a deal and will solve the problem here. Basically, though, I thought the whole idea was to put EVERYTHING into a single jar file and that anything else was discouraged. Is that true? Or is there no hard and fast rule on that and it's a case by case situation?

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