private static void createTestIndex() throws Exception {
        // Create index with custom analyzers
        Settings indexSettings = Settings.builder()
                .put("number_of_shards", 1)
                .put("number_of_replicas", 0)
                .put("analysis.analyzer.test_reading_analyzer.type", "custom")
                .put("analysis.analyzer.test_reading_analyzer.tokenizer", "standard")

    }

    /**
     * Sets the number of replicas for the OpenSearch index.
     *
     * @param numberOfReplicas The number of replicas.
     */
    public void setNumberOfReplicas(final int numberOfReplicas) {
        this.numberOfReplicas = numberOfReplicas;
    }

    /**
     * Sets the prefix length for generated document IDs.
     *
     * @param idPrefixLength The prefix length.

{
  "settings": {
    "index": {
      "codec": "${fess.index.codec}",
      "refresh_interval": "1s",
      "number_of_shards": "${fess.index.number_of_shards}",
      "number_of_replicas": 0,
      "auto_expand_replicas": "${fess.index.auto_expand_replicas}"
    },
    "analysis": {
      "char_filter": {
        "mapping_fa_filter": {
          "type": "mapping",
          "mappings_path": "${fess.dictionary.path}fa/mapping.txt"
        },