java.lang.AssertionError
   at org.netbeans.modules.masterfs.filebasedfs.children.ChildrenSupport.addChild(ChildrenSupport.java:125)
   at org.netbeans.modules.masterfs.filebasedfs.children.ChildrenSupport.rescanChild(ChildrenSupport.java:183)
   at org.netbeans.modules.masterfs.filebasedfs.children.ChildrenSupport.getChild(ChildrenSupport.java:103)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FolderObj$FolderChildrenCache.getChild(FolderObj.java:556)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObjectFactory.getFileObject(FileObjectFactory.java:181)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FolderObj.refreshImpl(FolderObj.java:370)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.BaseFileObj.refresh(BaseFileObj.java:677)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FolderObj.refresh(FolderObj.java:435)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObjectFactory.refresh(FileObjectFactory.java:511)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObjectFactory.refresh(FileObjectFactory.java:484)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObjectFactory.refreshAll(FileObjectFactory.java:431)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObjectFactory$1.run(FileObjectFactory.java:693)
   at org.netbeans.modules.masterfs.filebasedfs.FileBasedFileSystem.runAsInconsistent(FileBasedFileSystem.java:102)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObjectFactory$2.run(FileObjectFactory.java:705)
   at org.openide.filesystems.EventControl.runAtomicAction(EventControl.java:122)
   at org.openide.filesystems.FileSystem.runAtomicAction(FileSystem.java:539)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObjectFactory.refresh(FileObjectFactory.java:702)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.RootObj.invokeRefreshFor(RootObj.java:191)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.RootObj.setAttribute(RootObj.java:135)
   at org.openide.filesystems.FileUtil.refreshFor(FileUtil.java:155)
   at org.openide.filesystems.FileUtil$1.run(FileUtil.java:178)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.AssertionError
   at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:1453)
   at org.openide.filesystems.FileUtil.refreshAll(FileUtil.java:193)
   at org.apache.tools.ant.module.bridge.impl.BridgeImpl$2.run(BridgeImpl.java:344)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1415)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1954)