spring security 3 扩展 HttpSessionEventPublisher 统计在线用户数

 
<beans:bean id="defaultConcurrentSessionController"
ref="sessionRegistry" />
<beans:property name="exceptionIfMaximumExceeded" value="true" />
</beans:bean>

<beans:bean id="authenticationManager"
/>
</beans:list>
</beans:property>
<beans:property name="sessionController"
ref="defaultConcurrentSessionController" />
</beans:bean>
2.java中自动注入
@Autowired
SessionRegistry sessionRegistry;
@ModelAttribute("numUsers")
public int getNumberOfUsers() {
   return sessionRegistry.getAllPrincipals().size();
} 


确实是这样的，不知道有啥办法解决~