使用DWR出现Session error,控制台出现

A request has been denied as a potential CSRF attack.

这个错误是存在csrf(cross-site request forgeries,跨站请求伪造)攻击.

这必须将web.xml中配置dwr Servlet初始参数时必须设置这个参数

<init-param>
  <param-name>crossDomainSessionSecurity</param-name>
  <param-value>false</param-value>
</init-param>