java.lang.NullPointerException
    at org.netbeans.modules.java.execution.ExecProfileCustomizer$ClassSelectorPanel.initComponents(ExecProfileCustomizer.java:337)
    at org.netbeans.modules.java.execution.ExecProfileCustomizer$ClassSelectorPanel.<init>(ExecProfileCustomizer.java:306)
    at org.netbeans.modules.java.execution.ExecProfileCustomizer.jButton4ActionPerformed(ExecProfileCustomizer.java:238)
    at org.netbeans.modules.java.execution.ExecProfileCustomizer.access$100(ExecProfileCustomizer.java:52)
    at org.netbeans.modules.java.execution.ExecProfileCustomizer$1.actionPerformed(ExecProfileCustomizer.java:186)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1767)
    at javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(AbstractButton.java:1820)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:419)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:257)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:258)
    at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:227)
    at java.awt.Component.processMouseEvent(Component.java:5021)
    at java.awt.Component.processEvent(Component.java:4818)
    at java.awt.Container.processEvent(Container.java:1380)
    at java.awt.Component.dispatchEventImpl(Component.java:3526)
    at java.awt.Container.dispatchEventImpl(Container.java:1437)
    at java.awt.Component.dispatchEvent(Component.java:3367)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3214)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:2929)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:2859)
    at java.awt.Container.dispatchEventImpl(Container.java:1423)
    at java.awt.Window.dispatchEventImpl(Window.java:1566)
    at java.awt.Component.dispatchEvent(Component.java:3367)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:445)
[catch] at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:190)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:144)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:134)
    at java.awt.Dialog.show(Dialog.java:524)
    at org.netbeans.core.NbPresenter.superShow(NbPresenter.java:685)
    at org.netbeans.core.NbPresenter.run(NbPresenter.java:718)
    at org.openide.util.Mutex.doEventAccess(Mutex.java:913)
    at org.openide.util.Mutex.readAccess(Mutex.java:157)
    at org.netbeans.core.NbPresenter.show(NbPresenter.java:699)
    at java.awt.Component.show(Component.java:1128)
    at java.awt.Component.setVisible(Component.java:1083)
    at org.netbeans.core.NbTopManager$2.run(NbTopManager.java:395)
    at org.openide.util.Mutex$1.run(Mutex.java:927)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:171)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:443)
    at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:190)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:144)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:130)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:98)