docs: protected static boolean isChildOf(String parent, String child) {
        if (parent == null || child == null)
           return false;
        if (!child.startsWith((parent.endsWith(SEPARATOR) ? parent : parent + SEPARATOR)))
           return false;
        if (child.length() <= parent.length())
           return false;
        int from = parent.equals(SEPARATOR) ? parent.length() : parent.length() + 1;
        //  if(from-1 > child.length())
        // return false;
        String[] comps = Util.components(child.substring(from), SEPARATOR);
        return comps != null && comps.length <= 1;
     }