*
     * @param hash the encoded hash string to decode
     * @return the decoded hash string, or the original hash if decoding fails
     */
    public String decodeSimilarDocHash(final String hash) {
        if (hash != null && hash.startsWith(SIMILAR_DOC_HASH_PREFIX) && hash.length() > SIMILAR_DOC_HASH_PREFIX.length()) {
            try (BufferedReader reader = new BufferedReader(new InputStreamReader(

        assertEquals(hash, documentHelper.decodeSimilarDocHash(value));
        hash = "";
        value = "";
        assertEquals(hash, documentHelper.decodeSimilarDocHash(value));

        assertNull(documentHelper.decodeSimilarDocHash(null));
    }

    @Test
    public void test_appendLineNumber() {
        DocumentHelper documentHelper = new DocumentHelper();

                    context.addQuery(boolQuery -> {
                        boolQuery.filter(QueryBuilders.termQuery(fessConfig.getIndexFieldContentMinhashBits(),
                                documentHelper.decodeSimilarDocHash(similarDocHash)));
                    });
                }

                if (geoInfo != null && geoInfo.toQueryBuilder() != null) {