java.lang.NullPointerException: Attempted to pass a null filename to resolveFile
   at org.netbeans.spi.project.support.ant.AntProjectHelper.resolveFile(AntProjectHelper.java:1323)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl.registerSources(SourcesImpl.java:268)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl.initSources(SourcesImpl.java:227)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl.access$300(SourcesImpl.java:90)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl$1.run(SourcesImpl.java:143)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl$1.run(SourcesImpl.java:136)
   at org.netbeans.modules.openide.util.DefaultMutexImplementation.readAccess(DefaultMutexImplementation.java:209)
   at org.openide.util.Mutex.readAccess(Mutex.java:218)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl.getSourceGroups(SourcesImpl.java:136)
   at org.netbeans.spi.project.support.LookupProviderSupport$SourcesImpl.getSourceGroups(LookupProviderSupport.java:185)
   at org.netbeans.modules.project.ui.ProjectsRootNode$BadgingNode.setProjectFiles(ProjectsRootNode.java:761)
   at org.netbeans.modules.project.ui.ProjectsRootNode$BadgingNode.setProjectFiles(ProjectsRootNode.java:673)
   at org.netbeans.modules.project.ui.ProjectsRootNode$BadgingNode$2.run(ProjectsRootNode.java:614)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.NullPointerException: Attempted to pass a null filename to resolveFile
   at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:1484)
   at org.netbeans.modules.project.ui.ProjectsRootNode$BadgingNode.stateChanged(ProjectsRootNode.java:990)
   at org.openide.util.WeakListenerImpl$Change.stateChanged(WeakListenerImpl.java:356)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:133)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:119)
   at org.netbeans.spi.project.support.LookupProviderSupport$SourcesImpl.stateChanged(LookupProviderSupport.java:208)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:133)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:119)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl$FireAction.run(SourcesImpl.java:350)
   at org.netbeans.modules.openide.util.DefaultMutexImplementation.postRequest(DefaultMutexImplementation.java:996)
   at org.netbeans.modules.openide.util.DefaultMutexImplementation.postReadRequest(DefaultMutexImplementation.java:308)
   at org.openide.util.Mutex.postReadRequest(Mutex.java:371)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl.fireChange(SourcesImpl.java:327)
   at org.netbeans.modules.java.api.common.queries.SourcesImpl.propertyChange(SourcesImpl.java:335)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:215)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:263)
   at org.netbeans.modules.java.api.common.Roots.firePropertyChange(Roots.java:119)
   at org.netbeans.modules.java.api.common.SourceRoots.resetCache(SourceRoots.java:599)
   at org.netbeans.modules.java.api.common.SourceRoots.access$700(SourceRoots.java:100)
   at org.netbeans.modules.java.api.common.SourceRoots$ProjectMetadataListener.propertyChange(SourceRoots.java:695)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:215)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at org.netbeans.spi.project.support.ant.SequentialPropertyEvaluator.stateChanged(SequentialPropertyEvaluator.java:208)
   at org.openide.util.WeakListenerImpl$Change.stateChanged(WeakListenerImpl.java:356)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:133)
   at org.openide.util.ChangeSupport.fireChange(ChangeSupport.java:119)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$2.run(ProjectProperties.java:390)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$2.run(ProjectProperties.java:388)
   at org.netbeans.modules.openide.util.DefaultMutexImplementation.readAccess(DefaultMutexImplementation.java:209)
   at org.openide.util.Mutex.readAccess(Mutex.java:218)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$3.run(ProjectProperties.java:404)
   at org.openide.util.RequestProcessor$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)