private void workbookAdd() {
		Display display = new Display();
		Shell shell = new Shell(display);
		OleFrame frame = new OleFrame(shell, SWT.NONE);

		OleControlSite controlSite = new OleControlSite(frame, SWT.NONE, "Excel.Application");
		OleAutomation application = new OleAutomation(controlSite);
		controlSite.doVerb(OLE.OLEIVERB_INPLACEACTIVATE);

		// Set visible
		Variant[] arguments = new Variant[1];
		arguments[0] = new Variant("true");
		int[] ids = application.getIDsOfNames(new String[] { "Visible" });
		application.setProperty(ids[0], arguments);

		// Get Workbooks-Object
		int[] excelIds = application.getIDsOfNames(new String[] { "Workbooks" });
		Variant workbooksVariant = application.getProperty(excelIds[0]);
		OleAutomation workbooks = workbooksVariant.getAutomation();
		
		// Add new workbook
		int idAdd = workbooks.getIDsOfNames(new String[] { "Add" })[0];
		Variant add = workbooks.invoke(idAdd);
		OleAutomation workbook = add.getAutomation();

		//some things I'd like to do with "workbook"-object.
		//...
		//...
		
		// Close Excel
		int invokeID = application.getIDsOfNames(new String[] { "Quit" })[0];
		application.invokeNoReply(invokeID);
	}

int idAddIns = application.getIDsOfNames(new String[] {"COMAddIns"})[0];
        Variant addInsVar = application.getProperty(idAddIns);
        OleAutomation addIns = addInsVar.getAutomation();
        
        int countID = addIns.getIDsOfNames(new String[] {"Count"})[0];
        Variant countVariant = addIns.getProperty(countID);
                
        int addInsItemID = addIns.getIDsOfNames(new String[] {"Item"})[0];
        for (int i = 1; i <= countVariant.getInt(); i++) {
            Variant addInsItemVariant = addIns.invoke(addInsItemID, new Variant[] {new Variant(i)});
            OleAutomation addInsItem = addInsItemVariant.getAutomation();
            
            int addInsItemConnectID = addInsItem.getIDsOfNames(new String[] { "Connect" })[0];
            if (addInsItem.getProperty(addInsItemConnectID).getBoolean()) {
                int addInsItemNameID = addInsItem.getIDsOfNames(new String[] { "ProgId" })[0];
                Variant addInsItemNameVariant = addInsItem.getProperty(addInsItemNameID);
                String name = addInsItemNameVariant.getString();                
                addInsItem.setProperty(addInsItemConnectID, new Variant(false));
            }
        }