java.lang.IllegalStateException: Should not acquire Children.MUTEX while holding ProjectManager.mutex()
   at org.openide.nodes.Children$ProjectManagerDeadlockDetector.execute(Children.java:1918)
   at org.openide.util.Mutex.doWrapperAccess(Mutex.java:1328)
   at org.openide.util.Mutex.readAccess(Mutex.java:356)
   at org.openide.loaders.DataObject.getNodeDelegateImpl(DataObject.java:328)
   at org.openide.loaders.DataObject.getNodeDelegate(DataObject.java:320)
   at org.netbeans.modules.java.j2seplatform.platformdefinition.PlatformConvertor.create(PlatformConvertor.java:292)
   at org.netbeans.modules.java.j2seplatform.api.J2SEPlatformCreator.createJ2SEPlatformImpl(J2SEPlatformCreator.java:115)
   at org.netbeans.modules.java.j2seplatform.api.J2SEPlatformCreator.createJ2SEPlatform(J2SEPlatformCreator.java:74)
   at org.netbeans.modules.projectimport.eclipse.core.JavaPlatformSupport.getJavaPlatform(JavaPlatformSupport.java:126)
   at org.netbeans.modules.projectimport.eclipse.core.Importer.importProjectStage1(Importer.java:224)
   at org.netbeans.modules.projectimport.eclipse.core.Importer.access$600(Importer.java:72)
   at org.netbeans.modules.projectimport.eclipse.core.Importer$3.run(Importer.java:181)
   at org.netbeans.modules.projectimport.eclipse.core.Importer$3.run(Importer.java:178)
   at org.openide.util.Mutex.writeAccess(Mutex.java:399)
   at org.netbeans.modules.projectimport.eclipse.core.Importer.importProject(Importer.java:178)
   at org.netbeans.modules.projectimport.eclipse.core.Importer.access$200(Importer.java:72)
   at org.netbeans.modules.projectimport.eclipse.core.Importer$1.run(Importer.java:111)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1432)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2042)