- * 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. - *
- * 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. - *
- * 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. - *
- * 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. - *
- * Credits:
- *
Steven Spencer, JavaWorld magazine (Java Tip 66)
- *
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 (ejalbert@cs.stanford.edu)
- * @version 1.4b1 (Released June 20, 2001)
- */
-public class EjAlbertBrowserLauncher {
-
- /**
- * 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.
- *
- * Note that if this is false, openURL() 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 true if all intialization succeeded
- * false 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[] { EjAlbertBrowserLauncher.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");
- openURLm = 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 {
- openURLm.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