static {
   Map<String, String> fakeData = new HashMap<>();
   fakeData.put("http://www.weather.gov", "Weather forecast");
   fakeData.put("http://www.espn.com", "Sports scores");
   fakeData.put("http://www.marketwatch.com", "Stock market data");
   fakeData.put("http://www.fandango.com", "Movie showtimes");
   data = Collections.unmodifiableMap(fakeData);
 }
 /**
  * Returns an unmodifiable map of all metrics and their names.
  *
  * @return an unmodifiable map of all metrics and their names
  */
 public Map<MetricName, Metric> getAllMetrics() {
   return Collections.unmodifiableMap(metrics);
 }