org.netbeans.editor.GuardedException: Attempt to remove from guarded block at position 4,272.
   at org.netbeans.editor.GuardedDocument.preRemoveCheck(GuardedDocument.java:291)
   at org.netbeans.editor.BaseDocument.handleRemove(BaseDocument.java:930)
   at org.netbeans.editor.BaseDocument$FilterBypassImpl.remove(BaseDocument.java:2362)
   at javax.swing.text.DocumentFilter.remove(DocumentFilter.java:79)
   at org.openide.text.CloneableEditorSupport$DocFilter.remove(CloneableEditorSupport.java:3027)
   at org.netbeans.editor.BaseDocument.remove(BaseDocument.java:894)
   at org.netbeans.api.java.source.ModificationResult.processDocumentLocked(ModificationResult.java:406)
   at org.netbeans.api.java.source.ModificationResult.access$100(ModificationResult.java:95)
   at org.netbeans.api.java.source.ModificationResult$3.run(ModificationResult.java:371)
   at org.netbeans.editor.GuardedDocument.runAtomicAsUser(GuardedDocument.java:347)
   at org.openide.text.NbDocument.runAtomicAsUser(NbDocument.java:462)
Caused: java.io.IOException
   at org.netbeans.api.java.source.ModificationResult.processDocument(ModificationResult.java:391)
   at org.netbeans.api.java.source.ModificationResult.commit2(ModificationResult.java:333)
   at org.netbeans.api.java.source.ModificationResult.access$000(ModificationResult.java:95)
   at org.netbeans.api.java.source.ModificationResult$2.run(ModificationResult.java:241)
   at org.netbeans.editor.GuardedDocument.runAtomic(GuardedDocument.java:317)
   at org.openide.text.NbDocument.runAtomic(NbDocument.java:436)
   at org.netbeans.api.java.source.ModificationResult.commit(ModificationResult.java:238)
   at org.netbeans.api.java.source.ModificationResult.commit(ModificationResult.java:201)
   at org.netbeans.modules.java.hints.ConvertAnonymousToInner$FixImpl.implement(ConvertAnonymousToInner.java:214)
   at org.netbeans.modules.java.hints.ConvertAnonymousToInnerAction.perform(ConvertAnonymousToInnerAction.java:79)
   at org.netbeans.modules.java.hints.infrastructure.HintAction.doPerform(HintAction.java:115)
   at org.netbeans.modules.java.hints.infrastructure.HintAction.actionPerformed(HintAction.java:88)
   at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
   at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
   at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
   at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
   at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
   at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833)
   at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877)
   at java.awt.Component.processMouseEvent(Component.java:6505)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
   at java.awt.Component.processEvent(Component.java:6270)
   at java.awt.Container.processEvent(Container.java:2229)
   at java.awt.Component.dispatchEventImpl(Component.java:4861)
   at java.awt.Container.dispatchEventImpl(Container.java:2287)
   at java.awt.Component.dispatchEvent(Component.java:4687)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4832)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4492)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4422)
   at java.awt.Container.dispatchEventImpl(Container.java:2273)
   at java.awt.Window.dispatchEventImpl(Window.java:2713)
   at java.awt.Component.dispatchEvent(Component.java:4687)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:707)
   at java.awt.EventQueue.access$000(EventQueue.java:101)
   at java.awt.EventQueue$3.run(EventQueue.java:666)
   at java.awt.EventQueue$3.run(EventQueue.java:664)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
   at java.awt.EventQueue$4.run(EventQueue.java:680)
   at java.awt.EventQueue$4.run(EventQueue.java:678)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:677)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:158)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)