java.lang.AssertionError
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl.loadIndexingContext(NexusRepositoryIndexerImpl.java:265)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl.access$400(NexusRepositoryIndexerImpl.java:163)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl$10.run(NexusRepositoryIndexerImpl.java:859)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl$10.run(NexusRepositoryIndexerImpl.java:857)
   at org.openide.util.Mutex.writeAccess(Mutex.java:436)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl.getVersions(NexusRepositoryIndexerImpl.java:857)
   at org.netbeans.modules.maven.indexer.api.RepositoryQueries.getVersions(RepositoryQueries.java:154)
   at org.netbeans.modules.maven.repository.ui.BasicArtifactPanel$3.run(BasicArtifactPanel.java:521)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1424)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1968)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.AssertionError
   at org.openide.util.RequestProcessor.post(RequestProcessor.java:425)
   at org.netbeans.modules.maven.repository.ui.BasicArtifactPanel.componentOpened(BasicArtifactPanel.java:519)
   at org.netbeans.core.multiview.MultiViewPeer.showCurrentElement(MultiViewPeer.java:307)
   at org.netbeans.core.multiview.MultiViewPeer.peerComponentOpened(MultiViewPeer.java:255)
   at org.netbeans.core.multiview.MultiViewTopComponent.componentOpened(MultiViewTopComponent.java:138)
   at org.openide.windows.WindowManager.componentOpenNotify(WindowManager.java:307)
   at org.netbeans.core.windows.WindowManagerImpl.notifyTopComponentOpened(WindowManagerImpl.java:975)
   at org.netbeans.core.windows.Central.addModeOpenedTopComponent(Central.java:774)
   at org.netbeans.core.windows.ModeImpl.addOpenedTopComponent(ModeImpl.java:314)
   at org.netbeans.core.windows.WindowManagerImpl.topComponentOpenAtTabPosition(WindowManagerImpl.java:1083)
   at org.netbeans.core.windows.WindowManagerImpl.topComponentOpen(WindowManagerImpl.java:1050)
   at org.openide.windows.TopComponent.open(TopComponent.java:503)
   at org.openide.windows.TopComponent.open(TopComponent.java:483)
   at org.netbeans.modules.maven.indexer.api.ui.ArtifactViewer.showArtifactViewer(ArtifactViewer.java:129)
   at org.netbeans.modules.maven.indexer.api.ui.ArtifactViewer.showArtifactViewer(ArtifactViewer.java:95)
   at org.netbeans.modules.maven.api.CommonArtifactActions$ShowArtifactAction.actionPerformed(CommonArtifactActions.java:118)
   at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2028)
   at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2351)
   at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
   at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
   at javax.swing.AbstractButton.doClick(AbstractButton.java:389)
   at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1223)
   at com.apple.laf.AquaMenuItemUI.doClick(AquaMenuItemUI.java:137)
   at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1264)
   at java.awt.Component.processMouseEvent(Component.java:6352)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
   at java.awt.Component.processEvent(Component.java:6117)
   at java.awt.Container.processEvent(Container.java:2085)
   at java.awt.Component.dispatchEventImpl(Component.java:4714)
   at java.awt.Container.dispatchEventImpl(Container.java:2143)
   at java.awt.Component.dispatchEvent(Component.java:4544)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4621)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4282)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4212)
   at java.awt.Container.dispatchEventImpl(Container.java:2129)
   at java.awt.Window.dispatchEventImpl(Window.java:2478)
   at java.awt.Component.dispatchEvent(Component.java:4544)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:635)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:148)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)