java.lang.IllegalArgumentException: Duplicate in children list: LICENSE.txt
        at org.openide.filesystems.Ordering.getOrder(Ordering.java:97)
        at org.openide.filesystems.FileUtil.getOrder(FileUtil.java:1802)
        at org.openide.loaders.FolderChildren$1R.run(FolderChildren.java:161)
        at org.openide.loaders.FolderChildren.refreshChildren(FolderChildren.java:184)
        at org.openide.loaders.FolderChildren.addNotify(FolderChildren.java:269)
        at org.openide.nodes.Children.callAddNotify(Children.java:525)
        at org.openide.nodes.EntrySupport$Lazy.checkInit(EntrySupport.java:1020)
        at org.openide.nodes.EntrySupport$Lazy.getNodes(EntrySupport.java:1121)
        at org.openide.nodes.Children.getNodes(Children.java:425)
        at org.openide.nodes.FilterNode$Children$DefaultSupport.updateKeys(FilterNode.java:1550)
        at org.openide.nodes.FilterNode$Children$DefaultSupport.filterChildrenRemoved(FilterNode.java:1534)
        at org.openide.nodes.FilterNode$Children.filterChildrenRemoved(FilterNode.java:1448)
        at org.openide.nodes.FilterNode$ChildrenAdapter.childrenRemoved(FilterNode.java:1753)
        at org.openide.nodes.Node.fireSubNodesChange(Node.java:1043)
        at org.openide.nodes.Node$1.run(Node.java:459)
        at org.openide.util.Mutex.postRequest(Mutex.java:1251)
        at org.openide.util.Mutex.postWriteRequest(Mutex.java:582)
        at org.openide.nodes.Node.setChildren(Node.java:445)
        at org.netbeans.modules.java.jarloader.JarDataNode.access$200(JarDataNode.java:59)
        at org.netbeans.modules.java.jarloader.JarDataNode$DummyChildren.run(JarDataNode.java:108)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:572)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:997)