code: @Override
      public String getGeocodingKey() {
          if (geocodingKey != null) {
              return geocodingKey;
          }
          try (FileInputStream fileStream = new FileInputStream(fileName);
                  InputStreamReader iStreamReader =
                          new InputStreamReader(fileStream, "UTF-8");
                  BufferedReader br = new BufferedReader(iStreamReader);) {
              final StringBuilder sb = new StringBuilder();
              final String line = br.readLine();
              if (line != null) {
                  sb.append(line.replace("\n", ""));
              }
              geocodingKey = sb.toString();
              return geocodingKey;
          } catch (IOException e) {
              throw new GeoCodeRuntimeException(
                      "Couldn't open key file: " + fileName, e);
          }
      }
docs: {@inheritDoc}