/ptolemy/src/ptolemy/actor/gui/BrowserLauncher.java

/* Launch the user's default web browser.

 Copyright (c) 2002-2013 The Regents of the University of California.
 All rights reserved.
 Permission is hereby granted, without written agreement and without
 license or royalty fees, to use, copy, modify, and distribute this
 software and its documentation for any purpose, provided that the above
 copyright notice and the following two paragraphs appear in all copies
 of this software.

 IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
 FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
 THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
 SUCH DAMAGE.

 THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
 PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
 CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
 ENHANCEMENTS, OR MODIFICATIONS.

 PT_COPYRIGHT_VERSION_2
 COPYRIGHTENDKEY

 */
package ptolemy.actor.gui;

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;
import java.net.URL;

import ptolemy.util.StringUtilities;

/**
 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>

 <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>


 <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 Firefox via a shell command.</p>

 <blockquote>

 <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 is more out of curiosity than anything and is not required.  This
 software includes no warranty.  The author is not responsible for any
 loss of data or functionality or any adverse or unexpected effects of
 using this software.</p>

 <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
 </p>
 </blockquote>

 <p> On November 3, 2003, BrowserLauncher was downloaded from
 <a href="http://browserlauncher.sourceforge.net/">http://browserlauncher.sourceforge.net/</a>.
That URL no longer exists, there is a replacement package which is LGPL'd.
See <a href="http://web.archive.org/web/20031028032907/http://browserlauncher.sourceforge.net/"><code>http://web.archive.org/web/20031028032907/http://browserlauncher.sourceforge.net/</code></a> for the original web page.</p>



 @author Eric Albert (<a href="mailto:ejalbert@cs.stanford.edu">ejalbert@cs.stanford.edu</a>)
 @version $Id: BrowserLauncher.java 69510 2014-07-13 00:29:23Z cxh $, based on 1.4b1 (Released June 20, 2001)
 @since Ptolemy II 3.0
 @Pt.ProposedRating Red (cxh)
 @Pt.AcceptedRating Red (cxh)
 */
public class BrowserLauncher {
    /** Launch the browser on the first argument.  If there is
     *  no first argument, then open http://ptolemy.eecs.berkeley.edu.
     *  Second and subsequent arguments are ignored.
     *  It is best if the first argument is an absolute URL
     *  as opposed to a relative URL.
     *
     *  <p> For example, to open the user's default browser on
     *  http://www.eecs.berkeley.edu
     *  <pre>
     *  java -classpath $PTII ptolemy.actor.gui.BrowserLauncher http://www.eecs.berkeley.edu
     *  </pre>
     *  @param args An array of command line arguments.  The first
     *  argument names a URL to be opened.  If there is no first
     *  argument, then open http://ptolemy.eecs.berkeley.edu.  Second
     *  and subsequent arguments are ignored.
     *  @exception Exception If there is a problem launching the browser.
     */
    public static void main(String[] args) throws Exception {
        if (args.length >= 1) {
            // Ignore any arguments after the first one.
            BrowserLauncher.openURL(args[0]);
        } else {
            BrowserLauncher.openURL("http://ptolemy.eecs.berkeley.edu");
        }

        if (BrowserLauncher.delayExit) {
            System.out.println("Delaying exit for 10 seconds because we"
                    + "may have copied a jar: file");

            try {
                Thread.sleep(10000);
            } catch (InterruptedException e) {
            }

            StringUtilities.exit(0);
        }
    }

    /**
     * Attempts to open the default web browser to the given URL.
     *
     * <p> We use the following strategy to find URLs that may be inside
     * jar files:
     * <br> If the string does not start with "http": see if it is a
     * file.
     * <br> If the file cannot be found, look it up in the classpath.
     * <br> If the file can be found in the classpath then use the
     * found file instead of the given URL.
     * <br>If the file cannot be found in the classpath, then pass the
     * original given URL to the browser.
     * <p>If the ptolemy.ptII.browser property is set, then its value
     * is used as the value of the browser.
     * <br>To always use Internet Explorer, one might invoke Ptolemy
     * with:
     * <pre>
     * java -classpath $PTII -Dptolemy.ptII.browser=c:\\Program\ Files\\Internet\ Explorer\\iexplore.exe ptolemy.vergil.VergilApplication
     * </pre>
     * <p>To always use Firefox:
     * <pre>
     * java -classpath $PTII -Dptolemy.ptII.browser=c:\\Program\ Files\\Mozilla\ Firefox\\firefox ptolemy.vergil.VergilApplication
     * </pre>
     *
     * <p>To preserve your browser choice set the ptolemy.ptII.browser
     * property in <code>$PTII/lib/ptII.properties</code>.  Note that
     * each time <code>$PTII/bin/configure</code> is run,
     * <code>$PTII/lib/ptII.properties.in</code> is read and
     * <code>$PTII/lib/ptII.properties</code> is overwritten, so you
     * may want to add your changes to
co     * <code>$PTII/lib/ptII.properties.in</code>.
     *
     * @param url The URL to open.
     *  It is best if the first argument is an absolute URL
     *  as opposed to a relative URL.
     * @exception 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);
        }

        if (!url.startsWith("http:") && !url.startsWith("https:")) {
            // If the url does not start with http:, then look it up
            // as a regular file and then possibly in the classpath.
            File urlFile = null;

            try {
                urlFile = new File(url);
            } catch (Exception ex) {
                // Ignored, we try to fix this below.
                urlFile = null;
            }

            if (urlFile == null || !urlFile.exists()) {
                // The file could not be found, so try the search path mambo.
                // We might be in the Swing Event thread, so
                // Thread.currentThread().getContextClassLoader()
                // .getResource(entry) probably will not work.
                String refClassName = "ptolemy.kernel.util.NamedObj";

                try {
                    Class refClass = Class.forName(refClassName);
                    URL entryURL = refClass.getClassLoader().getResource(url);

                    if (entryURL != null && !url.startsWith("jar:")) {
                        System.out.println("BrowserLauncher: Could not "
                                + "find '" + url + "', but '" + entryURL
                                + "' was found.");
                        url = entryURL.toString();
                    } else {
                        if (url.startsWith("jar:")) {
                            // If the URL begins with jar: then we are
                            // inside Web Start and we should get the
                            // resource, write it to a temporary file
                            // and pass that value to the browser
                            // Save the jar file as a temporary file
                            // in the default platform dependent
                            // directory with the same suffix as that
                            // of the jar URL
                            // FIXME: we should probably cache this
                            // copy somehow.
                            String old = url;
                            String temporaryURL = JNLPUtilities
                                    .saveJarURLInClassPath(url);

                            if (temporaryURL != null) {
                                url = temporaryURL;
                            } else {
                                url = JNLPUtilities.saveJarURLAsTempFile(url,
                                        "tmp", null, null);
                                delayExit = true;
                            }

                            System.out.println("BrowserLauncher: Could not "
                                    + "find '" + old + "', but jar url'" + url
                                    + "' was found.");
                        }
                    }
                } catch (ClassNotFoundException ex) {
                    System.err.println("BrowserLauncher: Internal error, "
                            + " Could not find " + refClassName);
                }
            }
        }

        if (!StringUtilities.getProperty("ptolemy.ptII.browser").equals("")) {
            Runtime.getRuntime()
                    .exec(new String[] {
                            "\""
                                    + StringUtilities
                                            .getProperty("ptolemy.ptII.browser")
                                    + "\"", url });
            return;
        }

        Object browser = locateBrowser();

        if (browser == null) {
            throw new IOException("Unable to locate browser: " + errorMessage);
        }

        String args[];

        switch (jvm) {
        case MRJ_2_0:

            errorMessage = "Command was a call to aeDescConstructor(" + url
                    + ")";

            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 {
                // Encourage it to get disposed if it was created
                aeDesc = null;

                // Ditto
                browser = null;
            }

            break;

        case MRJ_2_1:
            args = new String[] { (String) browser, url };
            errorMessage = "Command was: " + args[0] + " " + args[1];
            Runtime.getRuntime().exec(args);
            break;

        case MRJ_3_0:

            errorMessage = "Command was a call to ICLaunchURL(" + url + ")";

            int[] instance = new int[1];
            int result = ICStart(instance, 0);

            if (result == 0) {
                int[] selectionStart = new int[] { 0 };
                byte[] urlBytes = url.getBytes("UTF-8");
                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:
            if (!url.startsWith("file:") && !url.startsWith("http:")
                    && !url.startsWith("https:")) {
                // Needed by Web Start file:
                // ptII/ptolemy/domains/ct/demo/CartPendulum/CartPendulum.jnlp
                url = new File(url).toURI().toURL().toString();
            }

            errorMessage = "Command was a call to openURL(" + url + ")";

            try {
                openURL.invoke(null, new Object[] { url });
            } catch (InvocationTargetException ite) {
                throw new IOException("InvocationTargetException while "
                        + "calling openURL() on " + url + " "
                        + ite.getMessage());
            } catch (IllegalAccessException iae) {
                throw new IOException("IllegalAccessException while "
                        + "calling openURL() on: " + url + " "
                        + iae.getMessage());
            }

            break;

        case WINDOWS_NT:
        case WINDOWS_9x:

            // Add quotes around the URL to allow ampersands and other special
            // characters to work.
            args = new String[] { (String) browser, FIRST_WINDOWS_PARAMETER,
                    SECOND_WINDOWS_PARAMETER, THIRD_WINDOWS_PARAMETER,
                    '"' + url + '"' };
            Process process = Runtime.getRuntime().exec(args);

            errorMessage = "Command was: "
                    + args[0]
                    + " "
                    + args[1]
                    + " "
                    + args[2]
                    + " "
                    + args[3]
                    + " "
                    + args[4]
                    + "\nNote: Under Windows, make sure that the file named by "
                    + "the url is executable.";

            // The return code returned by process.waitFor()
            // 0 usually indicates normal execution.
            int exitCode = 0;
            // 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 {
                exitCode = process.waitFor();
                process.exitValue();
            } catch (InterruptedException ie) {
                throw new IOException("InterruptedException while "
                        + "launching browser: " + ie.getMessage());
            }

            if (exitCode != 0) {
                throw new IOException(
                        "Process exec'd by BrowserLauncher returned "
                                + exitCode + "." + "\n url was: " + url
                                + "\n browser was: " + browser + "\n "
                                + errorMessage);
            }

            break;

        case OTHER:

            // Assume that we're on Unix and that firefox is installed
            // First, attempt to open the URL in a currently running
            // session of Netscape
            args = new String[] {
                    (String) browser,
                    NETSCAPE_REMOTE_PARAMETER,
                    NETSCAPE_OPEN_PARAMETER_START + url
                            + NETSCAPE_OPEN_PARAMETER_END };
            process = Runtime.getRuntime().exec(args);

            errorMessage = "Command was: " + args[0] + " " + args[1] + " "
                    + args[2];

            try {
                if (process.waitFor() != 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;
        }

    }

    /** Set to true if we copied a file out of a jar file so that
     *  the browser could display it.  The reason we need this flag
     *  is that the system will delete the temporary file on exit,
     *  and after openURL() is called, this Java process will exit
     *  unless we delay.
     */
    public static boolean delayExit = false;

    /**
     * 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 or firefox that opens a given
     * URL in an already-open copy of Netscape or firefox 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");
            if (mrjVersion == null) {
                // Java build 1.7.0_04-ea-b11 does not have the mrj.version property set.
                jvm = MRJ_3_1;
            } else {
                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() {
    }

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

    private native static int ICStart(int[] instance, int signature);

    private native static int ICStop(int[] instance);

    /**
     * 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 initialization 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 (String systemFolderFile : systemFolderFiles) {
                try {
                    File file = new File(systemFolder, systemFolderFile);

                    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())) {
                            // Actually the Finder, but that's OK
                            browser = file.toString();
                            return browser;
                        }
                    }
                } catch (IllegalArgumentException iare) {
                    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 = "firefox";
            break;
        }

        return browser;
    }
}