java.lang.IllegalArgumentException: len=-6 < 0
   at org.netbeans.editor.BaseDocument.handleRemove(BaseDocument.java:915)
   at org.netbeans.editor.BaseDocument$FilterBypassImpl.remove(BaseDocument.java:2404)
   at javax.swing.text.DocumentFilter.remove(DocumentFilter.java:79)
   at org.openide.text.CloneableEditorSupport$DocFilter.remove(CloneableEditorSupport.java:3031)
   at org.netbeans.editor.BaseDocument.remove(BaseDocument.java:901)
   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)
   at org.netbeans.api.java.source.ModificationResult.processDocument(ModificationResult.java:385)
   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.refactoring.java.spi.JavaModificationResult.commit(JavaModificationResult.java:74)
   at org.netbeans.modules.refactoring.spi.RefactoringCommit.commit(RefactoringCommit.java:149)
   at org.netbeans.modules.refactoring.api.RefactoringSession.doRefactoring(RefactoringSession.java:148)
   at org.netbeans.modules.refactoring.spi.impl.ParametersPanel$9.run(ParametersPanel.java:479)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1452)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2032)