java.util.ConcurrentModificationException
   at java.util.LinkedHashMap$LinkedHashIterator.nextNode(LinkedHashMap.java:719)
   at java.util.LinkedHashMap$LinkedKeyIterator.next(LinkedHashMap.java:742)
   at net.sickill.off.common.OffListModel.removeFile(OffListModel.java:108)
   at net.sickill.off.netbeans.NetbeansProject.fileDeleted(NetbeansProject.java:230)
   at org.openide.filesystems.FCLSupport$DispatchEventWrapper.dispatchEventImpl(FCLSupport.java:181)
   at org.openide.filesystems.FCLSupport$DispatchEventWrapperSingle.dispatchAllEventsSync(FCLSupport.java:224)
   at org.openide.filesystems.FCLSupport$DispatchEventWrapper.dispatchEvent(FCLSupport.java:137)
   at org.openide.filesystems.FCLSupport.dispatchEvent(FCLSupport.java:105)
   at org.openide.filesystems.FileObject$ED.dispatch(FileObject.java:1398)
   at org.openide.filesystems.FileSystem$EventDispatcher.run(FileSystem.java:795)
   at org.openide.filesystems.EventControl.dispatchEvent(EventControl.java:84)
   at org.openide.filesystems.FileSystem.dispatchEvent(FileSystem.java:554)
   at org.openide.filesystems.FileObject.dispatchEvent(FileObject.java:644)
   at org.openide.filesystems.FileObject.fireFileDeletedEvent(FileObject.java:620)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.BaseFileObj.fireFileDeletedEvent(BaseFileObj.java:742)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FolderObj.refreshImpl(FolderObj.java:523)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.BaseFileObj.refresh(BaseFileObj.java:893)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FolderObj.refresh(FolderObj.java:562)
   at org.openide.filesystems.FileObject.refresh(FileObject.java:1219)
   at org.netbeans.modules.masterfs.watcher.Watcher$1.run(Watcher.java:438)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1443)
   at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:68)
   at org.openide.util.lookup.Lookups.executeWith(Lookups.java:303)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2058)