GWT Session timeout with Timer - gwt

Question

I am trying to implement session timeout with help of a GWT Timer which will make a RPC call to server to check whether the session is valid or expired by using lastaccessedtime. but every time i make a RPC call it updates the lastaccessedtime (understandable as i am making a RPC call), any way i can prevent my Timer RPC call from updating the lastaccessedtime?
wrote some server side logic to get the lastaccessedtime and try to find out session is valid or not
com.google.gwt.user.client.Timer elapsedTimer;
public void onModuleLoad() {
elapsedTimer = new Timer () {
public void run() {
validateSession();
}};
//giving time delay of 1sec to call the batches
elapsedTimer.scheduleRepeating(60000);
}
public void validateSession(){
//Problem code every time i make this call it updates the last accessed time
viewService.validateSessionGWT(new AsyncCallback<ModuleData>() {
#Override
public void onFailure(Throwable e) {
//do something
}
#Override
public void onSuccess(ModuleData data) {
if(data.getSessionExpired()){
//redirect to login page
}
}
});
}
any idea how to overcome this problem or any other idea to implement Session management in GWT
NOTE: already gone through this which is similar to my approach
https://itsecrets.wordpress.com/2011/07/20/session-timeouts-with-gwt-rpc-calls/

Answer 1

Your GWT servlets extend the RemoteServiceServlet. So you can override processPost and add a custom last call timestamp in you http session. Every request updates this field.
I suggest to implement an abstract servlet that is extended by all your gwt servlets. Additionally you should not only set the custom last access field, but check it just before and only call the super method if everything is fine.
Then your timer and the servlet request you already have should only check this Session field.
Perhaps not the best solution but this should work.