code: public Config addEventJournalConfig(EventJournalConfig eventJournalConfig) {
          final String mapName = eventJournalConfig.getMapName();
          final String cacheName = eventJournalConfig.getCacheName();
          if (StringUtil.isNullOrEmpty(mapName) && StringUtil.isNullOrEmpty(cacheName)) {
              throw new IllegalArgumentException("Event journal config should have either map name or cache name non-empty");
          }
          if (!StringUtil.isNullOrEmpty(mapName)) {
              mapEventJournalConfigs.put(mapName, eventJournalConfig);
          }
          if (!StringUtil.isNullOrEmpty(cacheName)) {
              cacheEventJournalConfigs.put(cacheName, eventJournalConfig);
          }
          return this;
      }
docs: Adds the event journal configuration. The configuration may apply to a map
  and/or cache. A non-empty value for {@link EventJournalConfig#getMapName()}
  means the configuration applies to maps and a non-empty value for
  {@link EventJournalConfig#getCacheName()} means the configuration
  applies to caches.
  The returned name may be a pattern with which the configuration
  will be obtained in the future.
  
  @param eventJournalConfig the event journal configuration
  @return this config instance
  @throws IllegalArgumentException if the
  {@link EventJournalConfig#getMapName()} and
  {@link EventJournalConfig#getCacheName()}
  are both empty