почему мы получаем AssertionFailedError?

У меня есть следующая часть кода:

        TableViewer tv = new TableViewer(attributeTable);
        tv.setContentProvider(new BOAttributeTableContentProvider());
        tv.setLabelProvider(new BOAttributeTableLabelProvider());

где при установке поставщика маркировки я добираюсь AssertionFailedError. кто-либо может сказать мне, что неправильно я делаю здесь? или, в этом случае это бросает эту ошибку?

журнал ошибок:

org.eclipse.jface.util.Assert$AssertionFailedException: null argument;
    at org.eclipse.jface.util.Assert.isNotNull(Assert.java:150)
    at org.eclipse.jface.util.Assert.isNotNull(Assert.java:126)
    at org.eclipse.jface.viewers.StructuredViewer.disassociate(StructuredViewer.java:615)
    at org.eclipse.jface.viewers.TableViewer.internalRefreshAll(TableViewer.java:904)
    at org.eclipse.jface.viewers.TableViewer.internalRefresh(TableViewer.java:818)
    at org.eclipse.jface.viewers.TableViewer.internalRefresh(TableViewer.java:807)
    at org.eclipse.jface.viewers.StructuredViewer$7.run(StructuredViewer.java:1388)
    at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1323)
    at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:1386)
    at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:1345)
    at org.eclipse.jface.viewers.ContentViewer.setLabelProvider(ContentViewer.java:281)
    at org.eclipse.jface.viewers.StructuredViewer.setLabelProvider(StructuredViewer.java:2003)
    at org.eclipse.jface.viewers.TableViewer.setLabelProvider(TableViewer.java:1086)
    at com.misys.bankfusion.bpdesigner.boeditor.pages.BOAttributesPage.populateAttributeTableContents(BOAttributesPage.java:458)
    at com.misys.bankfusion.bpdesigner.boeditor.pages.BOAttributesPage.access$000(BOAttributesPage.java:128)
    at com.misys.bankfusion.bpdesigner.boeditor.pages.BOAttributesPage$1.setToModel(BOAttributesPage.java:341)
    at com.trapedza.bankfusion.editor.AbstractEditorDelegate.updateData(AbstractEditorDelegate.java:173)
    at com.trapedza.bankfusion.editor.AbstractEditorDelegate$1.dialogFieldChanged(AbstractEditorDelegate.java:181)
    at com.trapedza.bankfusion.utils.dialogs.internal.DialogField.dialogFieldChanged(DialogField.java:132)
    at com.trapedza.bankfusion.utils.dialogs.internal.ListBoxDialogField.doModifySelection(ListBoxDialogField.java:51)
    at com.trapedza.bankfusion.utils.dialogs.internal.ComboDialogField$2.widgetSelected(ComboDialogField.java:153)
    at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:90)
    at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:928)
    at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3348)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2968)
    at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1930)
    at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1894)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:422)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.eclipse.ui.internal.ide.IDEApplication.run(IDEApplication.java:95)
    at org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:78)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:92)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:68)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:177)
    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:585)
    at org.eclipse.core.launcher.Main.invokeFramework(Main.java:336)
    at org.eclipse.core.launcher.Main.basicRun(Main.java:280)
    at org.eclipse.core.launcher.Main.run(Main.java:977)
    at org.eclipse.core.launcher.Main.main(Main.java:952)