@Override
  public Map<SocketAddress, Map<String, String>> getStats() {
    return getStats(null);
  }
Get all of the stats from all of the connections.

@return a Map of a Map of stats replies by SocketAddress
@throws IllegalStateException in the rare circumstance where queue is too
          full to accept any more requests
src/main/java/net/spy/memcached/MemcachedClient.java