java.lang.NullPointerException
   at org.netbeans.modules.maven.nodes.DependenciesNode$DependenciesComparator.compare(DependenciesNode.java:467)
   at org.netbeans.modules.maven.nodes.DependenciesNode$DependenciesComparator.compare(DependenciesNode.java:455)
   at java.util.TimSort.countRunAndMakeAscending(TimSort.java:351)
   at java.util.TimSort.sort(TimSort.java:216)
   at java.util.Arrays.sort(Arrays.java:1512)
   at java.util.ArrayList.sort(ArrayList.java:1454)
   at java.util.Collections.sort(Collections.java:175)
   at org.netbeans.modules.maven.nodes.DependenciesNode$DependenciesSet.list(DependenciesNode.java:218)
   at org.netbeans.modules.maven.nodes.DependenciesNodeFactory$NList.keys(DependenciesNodeFactory.java:92)
   at org.netbeans.spi.project.ui.support.NodeFactorySupport$DelegateChildren$1.run(NodeFactorySupport.java:202)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.NullPointerException
   at org.openide.util.RequestProcessor.post(RequestProcessor.java:420)
   at org.netbeans.spi.project.ui.support.NodeFactorySupport$DelegateChildren.addNotify(NodeFactorySupport.java:194)
   at org.openide.nodes.Children.callAddNotify(Children.java:575)
   at org.openide.nodes.EntrySupportDefault.getArray(EntrySupportDefault.java:650)
   at org.openide.nodes.EntrySupportDefault.getNodes(EntrySupportDefault.java:162)
   at org.openide.nodes.EntrySupportDefault.getNodesCount(EntrySupportDefault.java:176)
   at org.openide.nodes.Children.getNodesCount(Children.java:520)
   at org.netbeans.spi.project.ui.support.NodeFactorySupport$DelegateChildren.getNodesCount(NodeFactorySupport.java:229)
   at org.openide.nodes.FilterNode$Children$DefaultSupport.callGetNodesCount(FilterNode.java:1683)
   at org.openide.nodes.FilterNode$Children.getNodesCount(FilterNode.java:1634)
   at org.openide.explorer.view.TreeView$6.run(TreeView.java:988)
   at org.openide.util.RequestProcessor$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)