java.lang.NullPointerException
   at org.openide.util.Exceptions$AnnException.getMessage(Exceptions.java:238)
   at org.openide.util.Exceptions$AnnException.toString(Exceptions.java:321)
   at java.util.Objects.toString(Objects.java:157)
   at java.lang.Throwable.initCause(Throwable.java:456)
   at org.openide.util.Exceptions$AnnException.findOrCreate0(Exceptions.java:279)
   at org.openide.util.Exceptions$AnnException.findOrCreate(Exceptions.java:256)
   at org.openide.util.Exceptions.attachMessage(Exceptions.java:85)
   at org.openide.loaders.InstanceSupport.findClass(InstanceSupport.java:506)
Caused: java.lang.ClassNotFoundException: From file: MultiFileObject@259ed612[CslPlugins/text/x-puml/language.instance] due to: java.lang.NullPointerException
   at org.openide.loaders.InstanceSupport.instanceClass(InstanceSupport.java:162)
   at org.openide.loaders.InstanceDataObject$Ser.instanceClass(InstanceDataObject.java:1372)
   at org.openide.loaders.InstanceSupport.instanceCreate(InstanceSupport.java:214)
   at org.openide.loaders.InstanceDataObject$Ser.instanceCreate(InstanceDataObject.java:1442)
   at org.openide.loaders.InstanceDataObject.instanceCreate(InstanceDataObject.java:846)
   at org.netbeans.modules.csl.spi.DefaultDataLoadersBridge.createInstance(DefaultDataLoadersBridge.java:143)
   at org.netbeans.modules.csl.core.Language.createInstance(Language.java:309)
   at org.netbeans.modules.csl.core.Language.getGsfLanguage(Language.java:248)
   at org.netbeans.modules.csl.core.Language.hasOccurrencesFinder(Language.java:670)
   at org.netbeans.modules.csl.core.CslEditorKit.createActions(CslEditorKit.java:185)
   at org.netbeans.editor.BaseKit.addActionsToMap(BaseKit.java:949)
   at org.netbeans.editor.BaseKit.getActions(BaseKit.java:918)
   at org.netbeans.modules.options.editor.keymap.EditorBridge.initActionMap(EditorBridge.java:358)
   at org.netbeans.modules.options.editor.keymap.EditorBridge.getEditorActionsMap(EditorBridge.java:322)
   at org.netbeans.modules.options.editor.keymap.EditorBridge.getActions(EditorBridge.java:105)
   at org.netbeans.modules.options.keymap.KeymapModel$AL.run(KeymapModel.java:203)
   at org.netbeans.modules.options.keymap.KeymapModel.waitFinished(KeymapModel.java:768)
   at org.netbeans.modules.options.keymap.KeymapModel.ensureActionsLoaded(KeymapModel.java:739)
   at org.netbeans.modules.options.keymap.KeymapModel.isDuplicateId(KeymapModel.java:390)
   at org.netbeans.modules.options.keymap.ShortcutsFinderImpl.findActionForId(ShortcutsFinderImpl.java:99)
   at org.netbeans.core.options.keymap.api.KeyStrokeUtils.getKeyStrokesForAction(KeyStrokeUtils.java:241)
   at org.netbeans.core.output2.OutputTab$TabAction.getAcceleratorsFor(OutputTab.java:998)
   at org.netbeans.core.output2.OutputTab$TabAction.<init>(OutputTab.java:948)
   at org.netbeans.core.output2.OutputTab.createActions(OutputTab.java:901)
   at org.netbeans.core.output2.OutputTab.access$300(OutputTab.java:116)
   at org.netbeans.core.output2.OutputTab$2.run(OutputTab.java:823)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1432)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2042)