java.lang.NullPointerException
   at org.netbeans.modules.swingapp.AppFrameworkSupport.getApplicationClassName(AppFrameworkSupport.java:268)
   at org.netbeans.modules.swingapp.AppFrameworkSupport.getApplicationClassName(AppFrameworkSupport.java:196)
   at org.netbeans.modules.swingapp.ResourceUtils.getAppDesignResourceMap(ResourceUtils.java:151)
   at org.netbeans.modules.swingapp.ProjectCustomizerProvider$ApplicationPropertyChangeListener.propertyChange(ProjectCustomizerProvider.java:162)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
   at org.netbeans.spi.project.support.ant.SequentialPropertyEvaluator.stateChanged(SequentialPropertyEvaluator.java:208)
   at org.openide.util.WeakListenerImpl$Change.stateChanged(WeakListenerImpl.java:329)
   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$2.run(ProjectProperties.java:347)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$2.run(ProjectProperties.java:345)
   at org.openide.util.Mutex.readAccess(Mutex.java:288)
   at org.netbeans.spi.project.support.ant.ProjectProperties$PP$3.run(ProjectProperties.java:361)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1424)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1968)