* @return file representing the tool executable, or null if the tool cannot be found
     */
    String findTool(String toolName);

    /**
     * Let the toolchain decide if it matches requirements defined
     * in the toolchain plugin configuration.
     *
     * @param requirements key value pair, may not be {@code null}

   |
   | * provides: A list of key/value-pairs.
   |   Based on the toolchain-configuration in the pom.xml Maven will search for
   |   matching <provides/> configuration. You can decide for yourself which key-value
   |   pairs to use. Often used keys are 'version', 'vendor' and 'arch'. By default
   |   the version has a special meaning. If you configured in the pom.xml '1.5'

    /**
     * Retrieves a specific document by ID.
     *
     * @param id the document ID to retrieve
     * @return JSON response containing the document
     */
    // GET /api/admin/searchlist/doc/{doc_id}
    @Execute
    public JsonResponse<ApiResult> get$doc(final String id) {
        return asJson(new ApiDocResponse().doc(searchEngineClient.getDocument(fessConfig.getIndexDocumentUpdateIndex(), builder -> {

      },
      "expires": {
        "type": "date",
        "format": "date_optional_time"
      },
      "digest": {
        "type": "text",
        "index": false
      },
      "doc_id": {
        "type": "keyword"
      },
      "favorite_count": {
        "type": "long"
      },
      "filename": {
        "type": "keyword"
      },
      "filetype": {

                    return "expires";
                case FessConfig.INDEX_FIELD_URL:
                    return "url";
                case FessConfig.INDEX_FIELD_doc_id:
                    return "doc_id";
                case FessConfig.INDEX_FIELD_ID:
                    return "id";
                case FessConfig.INDEX_FIELD_VERSION:
                    return "_version";

      },
      "expires": {
        "type": "date",
        "format": "date_optional_time"
      },
      "digest": {
        "type": "text",
        "index": false
      },
      "doc_id": {
        "type": "keyword"
      },
      "favorite_count": {
        "type": "long"
      },
      "filename": {
        "type": "keyword"
      },
      "filetype": {

            @Override
            public String getIndexFieldId() {
                return "_id";
            }

            @Override
            public String getIndexFieldDocId() {
                return "doc_id";
            }

            @Override
            public String getIndexFieldBoost() {
                return "boost";
            }

            @Override

        return null // Nothing to do.
      }

      val now = backend.nanoTime()
      var minDelayNanos = Long.MAX_VALUE
      var readyTask: Task? = null
      var multipleReadyTasks = false

      // Decide what to run. This loop's goal wants to:
      //  * Find out what this thread should do (either run a task or sleep)
      //  * Find out if there's enough work to start another thread.

      },
      "expires": {
        "type": "date",
        "format": "date_optional_time"
      },
      "digest": {
        "type": "text",
        "index": false
      },
      "doc_id": {
        "type": "keyword"
      },
      "favorite_count": {
        "type": "long"
      },
      "filename": {
        "type": "keyword"
      },
      "filetype": {

        // Test with populated list
        List<Map<String, Object>> documentItems = new ArrayList<>();
        Map<String, Object> doc1 = new HashMap<>();
        doc1.put("title", "Test Document 1");
        doc1.put("content", "Test content 1");
        documentItems.add(doc1);

        Map<String, Object> doc2 = new HashMap<>();
        doc2.put("title", "Test Document 2");
        doc2.put("content", "Test content 2");