java.lang.NullPointerException
   at java.awt.Container.addImpl(Container.java:1097)
   at java.awt.Container.add(Container.java:417)
   at org.netbeans.modules.form.layoutdesign.support.SwingLayoutBuilder.createLayout(SwingLayoutBuilder.java:171)
   at org.netbeans.modules.form.layoutdesign.support.SwingLayoutBuilder.setupContainerLayout(SwingLayoutBuilder.java:108)
   at org.netbeans.modules.form.VisualReplicator.setupContainerLayout(VisualReplicator.java:900)
   at org.netbeans.modules.form.VisualReplicator.cloneComponent(VisualReplicator.java:827)
   at org.netbeans.modules.form.VisualReplicator.cloneComponent(VisualReplicator.java:804)
   at org.netbeans.modules.form.VisualReplicator.createClone(VisualReplicator.java:195)
   at org.netbeans.modules.form.VisualReplicator.createClone(VisualReplicator.java:183)
   at org.netbeans.modules.form.FormDesigner$6.run(FormDesigner.java:678)
   at org.netbeans.modules.form.FormLAF$2.run(FormLAF.java:293)
   at org.netbeans.modules.openide.util.NbMutexEventProvider$Event.doEventAccess(NbMutexEventProvider.java:138)
   at org.netbeans.modules.openide.util.NbMutexEventProvider$Event.readAccess(NbMutexEventProvider.java:98)
   at org.netbeans.modules.openide.util.LazyMutexImplementation.readAccess(LazyMutexImplementation.java:94)
   at org.openide.util.Mutex.readAccess(Mutex.java:250)
   at org.netbeans.modules.form.FormLAF.executeWithLookAndFeel(FormLAF.java:276)
   at org.netbeans.modules.form.FormDesigner.createFormView(FormDesigner.java:671)
   at org.netbeans.modules.form.actions.TestAction.createPreview(TestAction.java:191)
   at org.netbeans.modules.form.actions.TestAction.run(TestAction.java:158)
   at org.netbeans.modules.form.actions.TestAction.performAction(TestAction.java:134)
   at org.openide.util.actions.CallableSystemAction$1.run(CallableSystemAction.java:130)
   at org.openide.util.actions.ActionInvoker$1.run(ActionInvoker.java:95)
   at org.openide.util.actions.ActionInvoker.doPerformAction(ActionInvoker.java:116)
   at org.openide.util.actions.ActionInvoker.invokeAction(ActionInvoker.java:99)
   at org.openide.util.actions.CallableSystemAction.actionPerformed(CallableSystemAction.java:127)
   at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
   at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
   at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
   at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
   at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
   at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:289)
   at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:289)
   at java.awt.Component.processMouseEvent(Component.java:6535)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
   at java.awt.Component.processEvent(Component.java:6300)
   at java.awt.Container.processEvent(Container.java:2236)
   at java.awt.Component.dispatchEventImpl(Component.java:4891)
   at java.awt.Container.dispatchEventImpl(Container.java:2294)
   at java.awt.Component.dispatchEvent(Component.java:4713)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4888)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4525)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4466)
   at java.awt.Container.dispatchEventImpl(Container.java:2280)
   at java.awt.Window.dispatchEventImpl(Window.java:2750)
   at java.awt.Component.dispatchEvent(Component.java:4713)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
   at java.awt.EventQueue.access$500(EventQueue.java:97)
   at java.awt.EventQueue$3.run(EventQueue.java:709)
   at java.awt.EventQueue$3.run(EventQueue.java:703)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
   at java.awt.EventQueue$4.run(EventQueue.java:731)
   at java.awt.EventQueue$4.run(EventQueue.java:729)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:159)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)