java.lang.NoClassDefFoundError: Could not initialize class org.netbeans.modules.masterfs.filebasedfs.FileBasedFileSystem
        at org.netbeans.modules.masterfs.filebasedfs.FileBasedURLMapper.getFileObjects(FileBasedURLMapper.java:128)
        at org.netbeans.modules.masterfs.MasterURLMapper.getFileObjects(MasterURLMapper.java:62)
        at org.openide.filesystems.URLMapper.findFileObject(URLMapper.java:213)
        at org.openide.filesystems.FileUtil.toFileObject(FileUtil.java:887)
        at org.openide.filesystems.FileUtil.getDiskFileSystemFor(FileUtil.java:126)
        at org.openide.filesystems.FileUtil.refreshFor(FileUtil.java:146)
        at org.openide.filesystems.FileUtil.refreshAll(FileUtil.java:162)
        at org.netbeans.core.ui.warmup.MenuWarmUpTask$NbWindowsAdapter.run(MenuWarmUpTask.java:160)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:577)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1030)
Caused: org.openide.util.RequestProcessor$Item: task failed due to: java.lang.NoClassDefFoundError: Could not initialize class org.netbeans.modules.masterfs.filebasedfs.FileBasedFileSystem
        at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:630)
        at org.netbeans.core.ui.warmup.MenuWarmUpTask$NbWindowsAdapter.windowActivated(MenuWarmUpTask.java:133)
        at java.awt.AWTEventMulticaster.windowActivated(AWTEventMulticaster.java:373)
        at java.awt.AWTEventMulticaster.windowActivated(AWTEventMulticaster.java:372)
        at java.awt.Window.processWindowEvent(Window.java:1874)
        at javax.swing.JFrame.processWindowEvent(JFrame.java:279)
        at java.awt.Window.processEvent(Window.java:1820)
        at java.awt.Component.dispatchEventImpl(Component.java:4583)
        at java.awt.Container.dispatchEventImpl(Container.java:2099)
        at java.awt.Window.dispatchEventImpl(Window.java:2475)
        at java.awt.Component.dispatchEvent(Component.java:4413)
        at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1848)
        at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:889)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:409)
        at java.awt.Component.dispatchEventImpl(Component.java:4455)
        at java.awt.Container.dispatchEventImpl(Container.java:2099)
        at java.awt.Window.dispatchEventImpl(Window.java:2475)
        at java.awt.Component.dispatchEvent(Component.java:4413)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.SentEvent.dispatch(SentEvent.java:55)
        at java.awt.DefaultKeyboardFocusManager$DefaultKeyboardFocusManagerSentEvent.dispatch(DefaultKeyboardFocusManager.java:183)
        at java.awt.DefaultKeyboardFocusManager.sendMessage(DefaultKeyboardFocusManager.java:210)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:286)
        at java.awt.Component.dispatchEventImpl(Component.java:4455)
        at java.awt.Container.dispatchEventImpl(Container.java:2099)
        at java.awt.Window.dispatchEventImpl(Window.java:2475)
        at java.awt.Component.dispatchEvent(Component.java:4413)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.SequencedEvent.dispatch(SequencedEvent.java:101)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)