Quadcap Embeddable Server

luxor/browser/albert/BrowserLauncher.java

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/*
** Luxor - XML User Interface Language (XUL) Toolkit
** Copyright (c) 2001, 2002 by Gerald Bauer
**
** This program is free software.
**
** You may redistribute it and/or modify it under the terms of the GNU
** General Public License as published by the Free Software Foundation.
** Version 2 of the license should be included with this distribution in
** the file LICENSE, as well as License.html. If the license is not
** included with this distribution, you may find a copy at the FSF web
** site at 'www.gnu.org' or 'www.fsf.org', or you may write to the
** Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139 USA.
**
** THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY OF ANY KIND,
** NOT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY. THE AUTHOR
** OF THIS SOFTWARE, ASSUMES _NO_ RESPONSIBILITY FOR ANY
** CONSEQUENCE RESULTING FROM THE USE, MODIFICATION, OR
** REDISTRIBUTION OF THIS SOFTWARE.
**
*/

package luxor.browser.albert;

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

/**
 *  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)
 */
public class BrowserLauncher
{

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

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

   /**
    *  The first parameter that needs to be passed into Runtime.exec() to open
    *  the default web browser on Windows.
    */
   private final static String FIRST_WINDOWS_PARAMETER = "/c";

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

   /**
    *  The framework to reference on Mac OS X
    */
   private final static String JDirect_MacOSX = "/System/Library/Frameworks/Carbon.framework/Frameworks/HIToolbox.framework/HIToolbox";

   /**
    *  JVM constant for MRJ 2.0
    */
   private final static int MRJ_2_0 = 0;

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

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

   /**
    *  JVM constant for MRJ 3.1
    */
   private final static int MRJ_3_1 = 4;
   private final static String NETSCAPE_OPEN_PARAMETER_END = ")'";
   private final static String NETSCAPE_OPEN_PARAMETER_START = "'openURL(";

   /**
    *  The shell parameters for Netscape that opens a given URL in an
    *  already-open copy of Netscape on many command-line systems.
    */
   private final static String NETSCAPE_REMOTE_PARAMETER = "-remote";

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

   /**
    *  The second parameter for Runtime.exec() on Windows.
    */
   private final static 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 final static String THIRD_WINDOWS_PARAMETER = "\"\"";

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

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

   /**
    *  The com.apple.MacOS.AEDesc class
    */
   private static Class aeDescClass;


   /**
    *  The <init>(String) method of com.apple.MacOS.AEDesc
    */
   private static Constructor aeDescConstructor;

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

   /**
    *  The message from any exception thrown throughout the initialization
    *  process.
    */
   private static String errorMessage;

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

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

   /**
    *  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 linkage object required for JDirect 3 on Mac OS X.
    */
   private static Object linkage;

   /**
    *  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 makeOSType method of com.apple.MacOS.OSUtils
    */
   private static Method makeOSType;

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

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

   /**
    *  The openURL method of com.apple.mrj.MRJFileUtils
    */
   private static Method openURL;

   /**
    *  The putParameter method of com.apple.MacOS.AppleEvent
    */
   private static Method putParameter;

   /**
    *  The sendNoReply method of com.apple.MacOS.AppleEvent
    */
   private static Method sendNoReply;

   /**
    *  This class should be never be instantiated; this just ensures so.
    */
   private BrowserLauncher() { }

   /**
    *  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;
      }
   }

   private native static int ICLaunchURL( int instance, byte[] hint, byte[] data, int len,
         int[] selectionStart, int[] selectionEnd );

   /**
    *  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 );

   /**
    *  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;
   }

   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();
      }
   }
}