Spring会话和websockets：会话未存储在会话存储库中

Question

我有一个Spring Session和Spring Websockets的应用程序。我使用websocket handshake interceptor为websocket session设置属性

public class WebsocketHandshakeInterceptor implements HandshakeInterceptor {


@Override
public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response,
                               WebSocketHandler wsHandler, Map<String, Object> attributes) throws Exception {
    if (request instanceof ServletServerHttpRequest) {
        ServletServerHttpRequest servletRequest = (ServletServerHttpRequest) request;
        HttpSession session = servletRequest.getServletRequest().getSession(true);
        if (session != null) {
            attributes.put(ApplicationConstants.HTTP_SESSION_ID_KEY, session.getId());
            attributes.put(ApplicationConstants.HTTP_SESSION_KEY, session);
        }
    }
    return true;
}

@Override
public void afterHandshake(ServerHttpRequest request, ServerHttpResponse response,
                           WebSocketHandler wsHandler, Exception ex) {
}

}

然后我抓住了SessionConnectEvent。事件包含所需信息（http会话和会话ID）。但会话在null

中为sessionRepository

@Component
public class WebSocketListener implements ApplicationListener<SessionConnectEvent> {

@Autowired
private MapSessionRepository sessionManager;

@Override
public void onApplicationEvent(SessionConnectEvent event) {
    String httpSessionId
            = event.getWebSocketSession().getAttributes().get(ApplicationConstants.HTTP_SESSION_ID_KEY).toString();
    sessionManager.getSession(httpSessionId); //returns null
}
}

第一次调用返回null，如果我尝试重新连接，则返回有效会话。你能告诉我我的错误吗？感谢。