docs: public static int getIdentifier(Class<?> type, String name) {
          // See if the cache already contains this identifier
          Map<String, Integer> typeCache;
          if (!sIdentifierCache.containsKey(type)) {
              typeCache = new ConcurrentHashMap<String, Integer>();
              sIdentifierCache.put(type, typeCache);
          }
          else {
              typeCache = sIdentifierCache.get(type);
          }
  
          if (typeCache.containsKey(name)) {
              return typeCache.get(name);
          }
  
          // Retrieve the identifier
          try {
              Field field = type.getField(name);
              int resId = field.getInt(null);
  
              if (resId != 0) {
                  typeCache.put(name, resId);
              }
  
              return resId;
          }
          catch (Exception e) {
              Log.e("JodaTimeAndroid", "Failed to retrieve identifier: type=" + type + " name=" + name, e);
              return 0;
          }
      }