If you are using JavaConfig and do not want to use XML you can create a HttpSessionListener and use getSession().setMaxInactiveInterval(), then in the Initializer add the listener in onStartup():
public class SessionListener implements HttpSessionListener {
@Override
public void sessionCreated(HttpSessionEvent event) {
System.out.println("session created");
event.getSession().setMaxInactiveInterval(15);
}
@Override
public void sessionDestroyed(HttpSessionEvent event) {
System.out.println("session destroyed");
}
}
Then in the Initializer:
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
super.onStartup(servletContext);
servletContext.addListener(new SessionListener());
}