code: public void createIndex(String index, boolean ignoreErrors, String indexSettings) throws IOException {
          logger.debug("create index [{}]", index);
          logger.trace("index settings: [{}]", indexSettings);
          CreateIndexRequest cir = new CreateIndexRequest(index);
          if (!isNullOrEmpty(indexSettings)) {
              cir.source(indexSettings, XContentType.JSON);
          }
          try {
              client.indices().create(cir, RequestOptions.DEFAULT);
          } catch (ElasticsearchStatusException e) {
              if (e.getMessage().contains("resource_already_exists_exception") && !ignoreErrors) {
                  throw new RuntimeException("index already exists");
              }
              if (!e.getMessage().contains("resource_already_exists_exception")) {
                  throw e;
              }
          }
          waitForHealthyIndex(index);
      }
docs: Create an index
  @param index index name
  @param ignoreErrors don't fail if the index already exists
  @param indexSettings index settings if any
  @throws IOException In case of error