docs: public MapSchema.MessageFactory getEnumMapFactory()
      {
          MapSchema.MessageFactory enumMapFactory = this.enumMapFactory;
          if (enumMapFactory == null)
          {
              synchronized (this)
              {
                  if ((enumMapFactory = this.enumMapFactory) == null)
                      this.enumMapFactory = enumMapFactory = newEnumMapFactory(this);
              }
          }
          return enumMapFactory;
      }