java.lang.NullPointerException
        at com.sun.org.apache.xerces.internal.impl.XMLEntityScanner.skipChar(XMLEntityScanner.java:1414)
        at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.skipSeparator(XMLDTDScannerImpl.java:2056)
        at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.scanDecls(XMLDTDScannerImpl.java:1959)
        at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.scanDTDExternalSubset(XMLDTDScannerImpl.java:320)
        at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.dispatch(XMLDocumentScannerImpl.java:1177)
        at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.next(XMLDocumentScannerImpl.java:1068)
        at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:988)
        at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:645)
        at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:140)
        at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:508)
        at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:807)
        at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
        at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:107)
        at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
        at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
        at org.netbeans.core.filesystems.DefaultParser.parse(DefaultParser.java:136)
        at org.netbeans.core.filesystems.XMLMIMEComponent$SniffingParser.sniff(XMLMIMEComponent.java:261)
        at org.netbeans.core.filesystems.XMLMIMEComponent.acceptFileObject(XMLMIMEComponent.java:80)
        at org.netbeans.core.filesystems.MIMEResolverImpl$FileElement.resolve(MIMEResolverImpl.java:428)
        at org.netbeans.core.filesystems.MIMEResolverImpl$FileElement.access$100(MIMEResolverImpl.java:410)
        at org.netbeans.core.filesystems.MIMEResolverImpl$Impl.findMIMEType(MIMEResolverImpl.java:139)
        at org.openide.filesystems.MIMESupport$CachedFileObject.resolveMIME(MIMESupport.java:253)
        at org.openide.filesystems.MIMESupport$CachedFileObject.getMIMEType(MIMESupport.java:241)
        at org.openide.filesystems.MIMESupport.findMIMEType(MIMESupport.java:115)
        at org.openide.filesystems.FileUtil.getMIMEType(FileUtil.java:1110)
        at org.netbeans.api.java.source.JavaSource.forFileObject(JavaSource.java:421)
        at org.netbeans.api.java.source.support.OpenedEditors.stateChanged(OpenedEditors.java:158)
        at org.netbeans.api.java.source.support.OpenedEditors$1.propertyChange(OpenedEditors.java:83)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
        at org.netbeans.api.editor.EditorRegistry.firePropertyChange(EditorRegistry.java:457)
        at org.netbeans.api.editor.EditorRegistry.focusLost(EditorRegistry.java:315)
        at org.netbeans.api.editor.EditorRegistry$FocusL.focusLost(EditorRegistry.java:560)
        at java.awt.AWTEventMulticaster.focusLost(AWTEventMulticaster.java:213)
        at java.awt.AWTEventMulticaster.focusLost(AWTEventMulticaster.java:212)
        at java.awt.Component.processFocusEvent(Component.java:5930)
        at java.awt.Component.processEvent(Component.java:5794)
        at java.awt.Container.processEvent(Container.java:2058)
        at java.awt.Component.dispatchEventImpl(Component.java:4410)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1848)
        at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:878)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:551)
        at java.awt.Component.dispatchEventImpl(Component.java:4282)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        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:177)
        at java.awt.DefaultKeyboardFocusManager.sendMessage(DefaultKeyboardFocusManager.java:204)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:616)
        at java.awt.Component.dispatchEventImpl(Component.java:4282)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Window.dispatchEventImpl(Window.java:2429)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.SequencedEvent.dispatch(SequencedEvent.java:98)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)