static Path appendIdPath(final Path path, final String id) {
        Path result = path;
        for (int i = 0; i < id.length() - PAD_SIZE; i += PAD_SIZE) {
            final String part = id.substring(i, i + PAD_SIZE);
            result = result.resolve(part);
        }
        return result;
    }
Given a string chop it up into parts and append to a path.
stroom-data/stroom-data-store-impl-fs/src/main/java/stroom/data/store/impl/fs/FsPrefixUtil.java