public static boolean isServletMappingConfigured(String servletName, MergeContext mergeContext) {
        return mergeContext.containsAttribute(createServletMappingKey(servletName));
    }
    public static boolean isServletMappingFromAnnotation(String servletName, MergeContext mergeContext) {
        ElementSource elementSource = (ElementSource) mergeContext.getAttribute(createServletMappingSourceKey(servletName));
        return elementSource != null && elementSource.equals(ElementSource.ANNOTATION);
    }