Eclipse - JAR creation failed "Class files on classpath not found or not accessible for..."

I have a project in Eclipse that has a red cross on it and will not export to a runnable JAR. I can't remember if I have looked at it since I reinstalled Windows on my laptop, but I know that I haven't changed any code. There are no errors in any of the classes, however the error I get points to the following class that deals with the menu items on Mac OSx: ``` import java.lang.reflect.*; public class osxhandler implements InvocationHandler { protected Object targetObject; protected Method targetMethod; protected String proxySignature; static Object macOSXApplication; // Pass this method an Object and Method equipped to perform application shutdown logic // The method passed should return a boolean stating whether or not the quit should occur public static void setQuitHandler(Object target, Method quitHandler) { setHandler(new HOsx("handleQuit", target, quitHandler)); } public static void setAboutHandler(Object target, Method aboutHandler) { boolean enableAboutMenu = (target != null && aboutHandler != null); if (enableAboutMenu) { setHandler(new HOsx("handleAbout", target, aboutHandler)); } // If we're setting a handler, enable the About menu item by calling // com.apple.eawt.Application reflectively try { Method enableAboutMethod = macOSXApplication.getClass().getDeclaredMethod("setEnabledAboutMenu", new Class[] { boolean.class }); enableAboutMethod.invoke(macOSXApplication, new Object[] { Boolean.valueOf(enableAboutMenu) }); } catch (Exception ex) { System.err.println("MacOSHandler could not access the About Menu"); ex.printStackTrace(); } } public static void setPreferencesHandler(Object target, Method prefsHandler) { boolean enablePrefsMenu = (target != null && prefsHandler != null); if (enablePrefsMenu) { setHandler(new HOsx("handlePreferences", target, prefsHandler)); } // If we're setting a handler, enable the Preferences menu item by calling // com.apple.eawt.Application reflectively try { Method enablePrefsMethod = macOSXApplication.getClass().getDeclaredMethod("setEnabledPreferencesMenu", new Class[] { boolean.class }); enablePrefsMethod.invoke(macOSXApplication, new Object[] { Boolean.valueOf(enablePrefsMenu) }); } catch (Exception ex) { System.err.println("MacOSHandler could not access the About Menu"); ex.printStackTrace(); } } // Pass this method an Object and a Method equipped to handle document events from the Finder // Documents are registered with the Finder via the CFBundleDocumentTypes dictionary in the // application bundle's Info.plist public static void setFileHandler(Object target, Method fileHandler) { setHandler(new HOsx("handleOpenFile", target, fileHandler) { // Override MacOSHandler.callTarget to send information on the // file to be opened public boolean callTarget(Object appleEvent) { if (appleEvent != null) { try { Method getFilenameMethod = appleEvent.getClass().getDeclaredMethod("getFilename", (Class[])null); String filename = (String) getFilenameMethod.invoke(appleEvent, (Object[])null); this.targetMethod.invoke(this.targetObject, new Object[] { filename }); } catch (Exception ex) { } } return true; } }); } // setHandler creates a Proxy object from the passed MacOSHandler and adds it as an ApplicationListener @SuppressWarnings({ "unchecked", "rawtypes" }) public static void setHandler(HOsx adapter) { try { Class applicationClass = Class.forName("com.apple.eawt.Application"); if (macOSXApplication == null) { macOSXApplication = applicationClass.getConstructor((Class[])null).newInstance((Object[])null); } Class applicationListenerClass = Class.forName("com.apple.eawt.ApplicationListener"); Method addListenerMethod = applicationClass.getDeclaredMethod("addApplicationListener", new Class[] { applicationListenerClass }); // Create a proxy object around this handler that can be reflectively added as an Apple ApplicationListener Object MacOSHandlerProxy = Proxy.newProxyInstance(HOsx.class.getClassLoader(), new Class[] { applicationListenerClass }, adapter); addListenerMethod.invoke(macOSXApplication, new Object[] { MacOSHandlerProxy }); } catch (ClassNotFoundException cnfe) { System.err.println("This version of Mac OS X does not support the Apple EAWT. ApplicationEvent handling has been disabled (" + cnfe + ")"); } catch (Exception ex) { // Likely a NoSuchMethodException or an IllegalAccessException loading/invoking eawt.Application methods System.err.println("Mac OS X Adapter could not talk to EAWT:"); ex.printStackTrace(); } } // Each MacOSHandler has the name of the EAWT method it intends to listen for (handleAbout, for example), // the Object that will ultimately perform the task, and the Method to be called on that Object protected HOsx(String proxySignature, Object target, Method handler) { this.proxySignature = proxySignature; this.targetObject = target; this.targetMethod = handler; } // Override this method to perform any operations on the event // that comes with the various callbacks // See setFileHandler above for an example public boolean callTarget(Object appleEvent) throws InvocationTargetException, IllegalAccessException { Object result = targetMethod.invoke(targetObject, (Object[])null); if (result == null) { return true; } return Boolean.valueOf(result.toString()).booleanValue(); } // InvocationHandler implementation // This is the entry point for our proxy object; it is called every time an ApplicationListener method is invoked public Object invoke (Object proxy, Method method, Object[] args) throws Throwable { if (isCorrectMethod(method, args)) { boolean handled = callTarget(args[0]); setApplicationEventHandled(args[0], handled); } // All of the ApplicationListener methods are void; return null regardless of what happens return null; } // Compare the method that was called to the intended method when the MacOSHandler instance was created // (e.g. handleAbout, handleQuit, handleOpenFile, etc.) protected boolean isCorrectMethod(Method method, Object[] args) { return (targetMethod != null && proxySignature.equals(method.getName()) && args.length == 1); } // It is important to mark the ApplicationEvent as handled and cancel the default behavior // This method checks for a boolean result from the proxy method and sets the event accordingly protected void setApplicationEventHandled(Object event, boolean handled) { if (event != null) { try { Method setHandledMethod = event.getClass().getDeclaredMethod("setHandled", new Class[] { boolean.class }); // If the target method returns a boolean, use that as a hint setHandledMethod.invoke(event, new Object[] { Boolean.valueOf(handled) }); } catch (Exception ex) { System.err.println("MacOSHandler was unable to handle an ApplicationEvent: " + event); ex.printStackTrace(); } } } } ``` Any ideas as to why I can't export/compile? I've never had this issue before.