java.lang.Exception: Scan canceled.
   at java.lang.Thread.getStackTrace(Thread.java:1567)
   at org.netbeans.modules.parsing.impl.indexing.LogContext.create(LogContext.java:74)
   at org.netbeans.modules.parsing.impl.indexing.LogContext.create(LogContext.java:67)
   at org.netbeans.modules.parsing.impl.indexing.PathRegistry.scheduleFirer(PathRegistry.java:813)
   at org.netbeans.modules.parsing.impl.indexing.PathRegistry.resetCacheAndFire(PathRegistry.java:808)
   at org.netbeans.modules.parsing.impl.indexing.PathRegistry.access$500(PathRegistry.java:84)
   at org.netbeans.modules.parsing.impl.indexing.PathRegistry$Listener.propertyChange(PathRegistry.java:1075)
   at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
   at org.netbeans.api.java.classpath.ClassPath.firePropertyChange(ClassPath.java:652)
   at org.netbeans.api.java.classpath.ClassPath$SPIListener.propertyChange(ClassPath.java:1119)
   at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:196)
   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.classpath.SourcePathImplementation.invalidate(SourcePathImplementation.java:120)
   at org.netbeans.modules.java.api.common.classpath.SourcePathImplementation.propertyChange(SourcePathImplementation.java:222)
   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:500)
   at org.netbeans.modules.java.api.common.SourceRoots.access$1500(SourceRoots.java:95)
   at org.netbeans.modules.java.api.common.SourceRoots$ProjectMetadataListener.configurationXmlChanged(SourceRoots.java:561)
   at sun.reflect.NativeMethodAccessorImpl.invoke0(NativeMethodAccessorImpl.java:0)
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
   at java.lang.reflect.Method.invoke(Method.java:601)
   at org.openide.util.WeakListenerImpl$ProxyListener.invoke(WeakListenerImpl.java:457)
   at $Proxy17.configurationXmlChanged(.java:0)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$3.run(AntProjectHelper.java:502)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$3.run(AntProjectHelper.java:497)
   at org.openide.util.Mutex.readAccess(Mutex.java:288)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.fireChange(AntProjectHelper.java:497)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.modifying(AntProjectHelper.java:523)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.access$900(AntProjectHelper.java:110)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$10.run(AntProjectHelper.java:964)
   at org.netbeans.spi.project.support.ant.AntProjectHelper$10.run(AntProjectHelper.java:937)
   at org.openide.util.Mutex.writeAccess(Mutex.java:397)
   at org.netbeans.spi.project.support.ant.AntProjectHelper.putConfigurationFragment(AntProjectHelper.java:937)
   at org.netbeans.spi.project.support.ant.ExtensibleMetadataProviderImpl.putConfigurationFragment(ExtensibleMetadataProviderImpl.java:90)
   at org.netbeans.modules.projectapi.AuxiliaryConfigImpl$2.run(AuxiliaryConfigImpl.java:150)
   at org.netbeans.modules.projectapi.AuxiliaryConfigImpl$2.run(AuxiliaryConfigImpl.java:141)
   at org.openide.util.Mutex.writeAccess(Mutex.java:397)
   at org.netbeans.modules.projectapi.AuxiliaryConfigImpl.putConfigurationFragment(AuxiliaryConfigImpl.java:141)
   at org.netbeans.modules.project.ui.ProjectUtilities.storeProjectOpenFiles(ProjectUtilities.java:496)
   at org.netbeans.modules.project.ui.ProjectUtilities.closeAllDocuments(ProjectUtilities.java:473)
   at org.netbeans.modules.project.ui.OpenProjectList.close(OpenProjectList.java:771)
   at org.netbeans.modules.project.ui.actions.CloseProject.actionPerformed(CloseProject.java:85)
   at org.netbeans.modules.project.ui.actions.CloseProject$1.run(CloseProject.java:78)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1404)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1984)