create checkbox in a table using docx4java

I am reading a docx template which has a table and generating docx document after populating the data. Can you throw some light on following items: a) I want to add checkbox in one of the columns of a table. I am generating a table. b) I have a checkbox which has a bookmark, i want to update its value. For e.g. bookmark value="MybkCheckbox" update checkbox value as checked.

Using following code i get the bookmark class object but how do i replace bookmark value

...

List<Object> bk= getAllElementFromObject(template.getMainDocumentPart(), CTBookmark.class);

...

private static List<Object> getAllElementFromObject(Object obj, Class<?> toSearch) {
    List<Object> result = new ArrayList<Object>();
    if (obj instanceof JAXBElement) obj = ((JAXBElement<?>) obj).getValue();

    if (obj.getClass().equals(toSearch))
        result.add(obj);
    else if (obj instanceof ContentAccessor) {
        List<?> children = ((ContentAccessor) obj).getContent();
        for (Object child : children) {
            result.addAll(getAllElementFromObject(child, toSearch));
        }

    }
    return result;
}