java.lang.IllegalStateException: Should not acquire Children.MUTEX while holding ProjectManager.mutex()
   at org.openide.nodes.Children$ProjectManagerDeadlockDetector.execute(Children.java:1829)
   at org.openide.util.Mutex.doWrapperAccess(Mutex.java:1323)
   at org.openide.util.Mutex.readAccess(Mutex.java:351)
   at org.openide.explorer.view.VisualizerNode$QP.run(VisualizerNode.java:685)
   at org.openide.util.Mutex.doEvent(Mutex.java:1338)
   at org.openide.util.Mutex.writeAccess(Mutex.java:452)
   at org.openide.explorer.view.VisualizerNode$QP.runSafe(VisualizerNode.java:667)
   at org.openide.explorer.view.VisualizerNode.propertyChange(VisualizerNode.java:426)
Caused: java.lang.reflect.InvocationTargetException
   at sun.reflect.GeneratedMethodAccessor20.invoke(GeneratedMethodAccessor20.java:0)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
   at java.lang.reflect.Method.invoke(Method.java:597)
   at org.openide.util.WeakListenerImpl$ProxyListener.invoke(WeakListenerImpl.java:456)
Caused: java.lang.reflect.UndeclaredThrowableException
   at $Proxy7.propertyChange(.java:0)
   at org.openide.nodes.Node.fireOwnPropertyChange(Node.java:1249)
   at org.openide.nodes.FilterNode$NodeAdapter.propertyChange(FilterNode.java:1202)
   at org.openide.nodes.FilterNode$NodeAdapter.propertyChange(FilterNode.java:1177)
   at org.openide.nodes.Node.fireOwnPropertyChange(Node.java:1249)
   at org.openide.nodes.Node.fireNameChange(Node.java:1035)
   at org.openide.nodes.FilterNode.changeOriginal(FilterNode.java:463)
   at org.netbeans.spi.java.project.support.ui.PackageView$RootNode.propertyChange(PackageView.java:282)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:193)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
   at org.netbeans.spi.project.support.ant.SourcesHelper$SourceRoot$Group.propertyChange(SourcesHelper.java:245)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:193)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
   at org.netbeans.modules.apisupport.project.Evaluator$2.run(Evaluator.java:243)
   at org.netbeans.modules.apisupport.project.Evaluator$2.run(Evaluator.java:226)
   at org.openide.util.Mutex.readAccess(Mutex.java:285)
   at org.netbeans.modules.apisupport.project.Evaluator.reset(Evaluator.java:226)
   at org.netbeans.modules.apisupport.project.Evaluator.configurationXmlChanged(Evaluator.java:264)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$3.run(AntProjectHelper.java:497)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$3.run(AntProjectHelper.java:492)
   at org.openide.util.Mutex.readAccess(Mutex.java:285)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.fireChange(AntProjectHelper.java:492)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.modifying(AntProjectHelper.java:518)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.access$900(AntProjectHelper.java:105)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$10.run(AntProjectHelper.java:956)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$10.run(AntProjectHelper.java:929)
   at org.openide.util.Mutex.writeAccess(Mutex.java:394)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.putConfigurationFragment(AntProjectHelper.java:929)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.putPrimaryConfigurationData(AntProjectHelper.java:818)
   at org.netbeans.modules.apisupport.project.NbModuleProject$3.run(NbModuleProject.java:363)
   at org.netbeans.modules.apisupport.project.NbModuleProject$3.run(NbModuleProject.java:357)
   at org.openide.util.Mutex.writeAccess(Mutex.java:394)
   at org.netbeans.modules.apisupport.project.NbModuleProject.putPrimaryConfigurationData(NbModuleProject.java:357)
   at org.netbeans.modules.apisupport.project.ProjectXMLManager.replaceClassPathExtensions(ProjectXMLManager.java:726)
   at org.netbeans.modules.apisupport.project.ui.customizer.SingleModuleProperties.storeProperties(SingleModuleProperties.java:962)
   at org.netbeans.modules.apisupport.project.ui.customizer.CustomizerProviderImpl.storeProperties(CustomizerProviderImpl.java:87)
   at org.netbeans.modules.apisupport.project.ui.customizer.BasicCustomizer$1.run(BasicCustomizer.java:159)
   at org.netbeans.modules.apisupport.project.ui.customizer.BasicCustomizer$1.run(BasicCustomizer.java:157)
   at org.openide.util.Mutex.writeAccess(Mutex.java:433)
   at org.netbeans.modules.apisupport.project.ui.customizer.BasicCustomizer.save(BasicCustomizer.java:157)
   at org.netbeans.modules.apisupport.project.ui.customizer.BasicCustomizer$OptionListener.actionPerformed(BasicCustomizer.java:180)
   at org.netbeans.modules.project.uiapi.CustomizerDialog$OptionListener$1.run(CustomizerDialog.java:246)
   at org.openide.util.Mutex.writeAccess(Mutex.java:394)
   at org.netbeans.modules.project.uiapi.CustomizerDialog$OptionListener.actionPerformed(CustomizerDialog.java:244)
   at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
   at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
   at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
   at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
   at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
   at java.awt.Component.processMouseEvent(Component.java:6263)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
   at java.awt.Component.processEvent(Component.java:6028)
   at java.awt.Container.processEvent(Container.java:2041)
   at java.awt.Component.dispatchEventImpl(Component.java:4630)
   at java.awt.Container.dispatchEventImpl(Container.java:2099)
   at java.awt.Component.dispatchEvent(Component.java:4460)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4574)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4238)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4168)
   at java.awt.Container.dispatchEventImpl(Container.java:2085)
   at java.awt.Window.dispatchEventImpl(Window.java:2478)
   at java.awt.Component.dispatchEvent(Component.java:4460)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:134)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)