protected boolean isServing(final Cache cache) {
    return !cache.getCacheServers().isEmpty();
  }
Determines whether the specified Cache has any CacheServers.

@param cache the Cache to check for existing CacheServers.
@return a boolean value indicating if any CacheServers were added to the Cache.
geode-core/src/main/java/org/apache/geode/distributed/ServerLauncher.java