/**
* 注册用户
*/
public void registerAuthentication(Authentication authentication) {
WebUserDetails details = (WebUserDetails) authentication.getDetails();
OnlineProfile profile = (OnlineProfile) profileMap.get(details.getCategory());
OnlineActivity existed = getOnlineActivity(details.getSessionId());
String sessionId = details.getSessionId();
Object principal = authentication.getPrincipal();
OnlineActivity newOne = OnlineActivityBuilder.build(principal, authentication.getDetails(),
sessionId, new Date());
// 原先没有的要占座
if (null == existed) {