browserlauncher.java

java实现的P2P多agent中间件

	private static boolean loadClasses() {
		switch (jvm) {
			case MRJ_2_0:
				try {
					Class aeTargetClass = Class.forName("com.apple.MacOS.AETarget");
					macOSErrorClass = Class.forName("com.apple.MacOS.MacOSError");
					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 });
					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;
		}
		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;
						}
						Object fileType = getFileType.invoke(null, new Object[] { file });
						if (FINDER_TYPE.equals(fileType.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 WINDOWS_NT:
				browser = "cmd.exe";
				break;
			case WINDOWS_9x:
				browser = "command.com";
				break;
			case WINDOWS_2000:
				browser ="";
				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 WINDOWS_NT:
		  case WINDOWS_9x:
				Runtime.getRuntime().exec(new String[] { (String)browser, FIRST_WINDOWS_PARAMETER,
																	SECOND_WINDOWS_PARAMETER, url });
		  
				break;
			case WINDOWS_2000:
				String cmd = "rundll32" + " " + "url.dll" + " " +  "FileProtocolHandler"+ " " + url; 
        Runtime.getRuntime().exec(cmd); 
				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 process = Runtime.getRuntime().exec((String) browser +
															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;
		}
	}
}