Java Development Tools

I'm getting following exception while exporting OSB configuration into a jar file

Unhandled event loop exception
org.eclipse.core.runtime.AssertionFailedException: null argument:
at org.eclipse.core.runtime.Assert.isNotNull(Assert.java:85)
at org.eclipse.core.runtime.Assert.isNotNull(Assert.java:73)
at org.eclipse.jface.viewers.StructuredViewer.assertElementsNotNull(StructuredViewer.java:593)
at org.eclipse.jface.viewers.StructuredViewer.getRawChildren(StructuredViewer.java:960)
at org.eclipse.jface.viewers.ColumnViewer.getRawChildren(ColumnViewer.java:703)
at org.eclipse.jface.viewers.AbstractTreeViewer.getRawChildren(AbstractTreeViewer.java:1330)
at org.eclipse.jface.viewers.TreeViewer.getRawChildren(TreeViewer.java:390)
at org.eclipse.jface.viewers.AbstractTreeViewer.getFilteredChildren(AbstractTreeViewer.java:636)
at org.eclipse.jface.viewers.AbstractTreeViewer.getSortedChildren(AbstractTreeViewer.java:602)
at org.eclipse.jface.viewers.AbstractTreeViewer$1.run(AbstractTreeViewer.java:799)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.eclipse.jface.viewers.AbstractTreeViewer.createChildren(AbstractTreeViewer.java:776)
at org.eclipse.jface.viewers.TreeViewer.createChildren(TreeViewer.java:640)
at org.eclipse.jface.viewers.AbstractTreeViewer.internalInitializeTree(AbstractTreeViewer.java:1490)
at org.eclipse.jface.viewers.TreeViewer.internalInitializeTree(TreeViewer.java:829)
at org.eclipse.jface.viewers.AbstractTreeViewer$5.run(AbstractTreeViewer.java:1474)
at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1392)
at org.eclipse.jface.viewers.TreeViewer.preservingSelection(TreeViewer.java:402)
at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1354)
at org.eclipse.jface.viewers.CheckboxTreeViewer.preservingSelection(CheckboxTreeViewer.java:418)
at org.eclipse.jface.viewers.AbstractTreeViewer.inputChanged(AbstractTreeViewer.java:1480)
at org.eclipse.jface.viewers.ContentViewer.setInput(ContentViewer.java:275)
at org.eclipse.jface.viewers.StructuredViewer.setInput(StructuredViewer.java:1639)
at com.bea.alsb.ui.repositories.jar.ConfigJarContentViewer.onContainerChanged(Unknown Source)
at com.bea.alsb.ui.repositories.jar.ConfigJarContentViewer.access$1(Unknown Source)
at com.bea.alsb.ui.repositories.jar.ConfigJarContentViewer$1.propertyChange(Unknown Source)
at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:347)
at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:278)
at com.bea.alsb.ui.containers.selection.ContainerSelector.fireSelectionEvent(Unknown Source)
at com.bea.alsb.ui.containers.selection.ContainerSelector.setSelectedContainer(Unknown Source)
at com.bea.alsb.ui.repositories.jar.ConfigJarContentViewer.<init>(Unknown Source)
at com.bea.alsb.ui.repositories.jar.JarContextWizardPage.createResourcesGroup(Unknown Source)
at com.bea.alsb.ui.repositories.jar.JarContextWizardPage.createControls(Unknown Source)
at com.bea.alsb.ui.repositories.common.BaseWizardPage.createControl(Unknown Source)
at com.bea.alsb.ui.repositories.jar.JarContextWizardPage.createControl(Unknown Source)
at org.eclipse.jface.wizard.Wizard.createPageControls(Wizard.java:170)
at org.eclipse.jface.wizard.WizardDialog.createPageControls(WizardDialog.java:677)
at org.eclipse.jface.wizard.WizardDialog.createContents(WizardDialog.java:549)
at org.eclipse.jface.window.Window.create(Window.java:431)
at org.eclipse.jface.dialogs.Dialog.create(Dialog.java:1090)
at org.eclipse.ui.internal.navigator.wizards.WizardShortcutAction.run(WizardShortcutAction.java:95)
at org.eclipse.jface.action.Action.runWithEvent(Action.java:499)
at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:584)
at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:501)
at org.eclipse.jface.action.ActionContributionItem$5.handleEvent(ActionContributionItem.java:411)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3910)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3504)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2405)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2369)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2221)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:500)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:493)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:119)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:194)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:368)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:559)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:515)
at org.eclipse.equinox.launcher.Main.run(Main.java:1312)
at org.eclipse.equinox.launcher.Main.main(Main.java:1287)