EDIT

    @Override

    public Object execute(ExecutionEvent event) throws ExecutionException {

        MPart part = partService.createPart(AppModelId.PARTDESCRIPTOR_EU_ETAXONOMY_TAXEDITOR_EDITOR_VIEW_DERIVATE_DERIVATEVIEW);

        partService.showPart(part, PartState.ACTIVATE);

        DerivateView derivateView = (DerivateView) part.getObject();

	@Override

	protected void open(ExecutionEvent event, SpecimenTypeDesignation entity) {

	    DerivateViewEditorInput input = new DerivateViewEditorInput(entity.getUuid());

	            AppModelId.PARTDESCRIPTOR_EU_ETAXONOMY_TAXEDITOR_EDITOR_VIEW_DERIVATE_DERIVATEVIEW, PartState.ACTIVATE);

	    DerivateView derivateView = (DerivateView) part.getObject();

	    derivateView.init(input);

        if(associatedSpecimenOrObservation!=null){

            UUID specimenUuid = associatedSpecimenOrObservation.getUuid();

            DerivateViewEditorInput input = new DerivateViewEditorInput(Collections.singletonList(specimenUuid));

                    AppModelId.PARTDESCRIPTOR_EU_ETAXONOMY_TAXEDITOR_EDITOR_VIEW_DERIVATE_DERIVATEVIEW, PartState.ACTIVATE);

            DerivateView derivateView = (DerivateView) part.getObject();

            derivateView.init(input);

    @Override

    protected void open(ExecutionEvent event, SpecimenOrObservationBase<?> entity) {

        DerivateViewEditorInput input = new DerivateViewEditorInput(entity.getUuid());

                AppModelId.PARTDESCRIPTOR_EU_ETAXONOMY_TAXEDITOR_EDITOR_VIEW_DERIVATE_DERIVATEVIEW, PartState.ACTIVATE);

        DerivateView derivateView = (DerivateView) part.getObject();

        derivateView.init(input);

            specimenUuids.add(specimenOrObservationBase.getUuid());

        }

        DerivateViewEditorInput input = new DerivateViewEditorInput(specimenUuids, taxonUuid);

                AppModelId.PARTDESCRIPTOR_EU_ETAXONOMY_TAXEDITOR_EDITOR_VIEW_DERIVATE_DERIVATEVIEW, PartState.ACTIVATE);

        DerivateView derivateView = (DerivateView) part.getObject();

        derivateView.init(input);

    @Override

    public Object execute(ExecutionEvent event) throws ExecutionException {

                eu.etaxonomy.taxeditor.bulkeditor.AppModelId.PARTDESCRIPTOR_EU_ETAXONOMY_TAXEDITOR_BULKEDITOR_REFERENCINGOBJECTS_E4_REFERENCINGOBJECTSVIEWE4,

                PartState.ACTIVATE);

        return null;

            IEditorPart activeEditor = getActivePage().getActiveEditor();

            Object activePart = getActivePage().getActivePart();

            if(activeEditor==null){

            }

            Object wrappedPart = WorkbenchUtility.getE4WrappedPart(activePart);

            return wrappedPart!=null?wrappedPart:activeEditor;

	public static String ID = "eu.etaxonomy.taxeditor.view.detail"; //$NON-NLS-1$

	private DetailsViewer viewer;

	private CdmBase lastObject;

	private Object lastPart;

	    try{

	        boolean isSelectionProvidingPartStillActive = false;

	        if(selectionProvidingPart!=null){

	            Collection<MPart> parts = partService.getParts();

	            for (MPart mPart : parts) {

	                Object object = mPart.getObject();

	@Override

	public void showEmptyPage() {

	    viewer.setSelection(null);

	    super.showEmptyPage();

	}

    }

    @Override

    public void showViewer(Object part, IStructuredSelection selection){

    	this.part = part;

        Object element = selection.getFirstElement();

//        if (part == lastPart && element == lastObject ){

//        	getViewer().setInput(element);

//        	return;