Spring boot and #SessionAttributes - session

Question

I'm working on an app with Spring Boot 1.2.5 RELEASE and having a problem that's difficult to replicate, and seems to be related to my session. Doing lots of research indicates that when using the #SessionAttribute annotation my session will end when my web page accesses another controller. Although I also found some information that indicates this is no longer true with the most recent Spring Boot. Also, the other controller does not use the same template or session identifier as this controller.
Alternatively I think my session may be expiring, but I can't seem to find any information talking about a default time out.
The app is straightforward, just a web page to edit form data. Sometimes when the save button is clicked an exception is thrown saying something to the effect that "adminForm" is not valid model data. I'm sorry I have been unable to replicate the exception and had not saved it.
The code is below, thanks in advance for your comments.
#SessionAttributes("adminForm")
#Controller
public class Admin_FormController
{
final static protected long INDEX_RA = 1L;
#Autowired
private AdminDataRepository rep;
#RequestMapping(value="/admin", method=RequestMethod.GET)
public String adminForm(Model model)
{
AdminData ad = rep.findById(INDEX_RA);
// If there is no configuration record, create one and assign the primary key
if(ad == null)
{
ad = new AdminData();
ad.setId(INDEX_RA);
}
model.addAttribute("adminForm", ad);
return "adminForm";
}
#RequestMapping(value="/admin", method=RequestMethod.POST)
public #ResponseBody AdminData adminSubmit(#ModelAttribute("adminForm") AdminData ad, Model model)
{
rep.save(ad);
model.addAttribute("adminForm", ad);
return ad;
}
}
UPDATE:
Here is the exception that is thrown:
2015-07-28 11:12:16.564 ERROR 52963 --- [nio-8080-exec-3] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Expected session attribute 'adminForm'] with root cause
org.springframework.web.HttpSessionRequiredException: Expected session attribute 'adminForm'
at org.springframework.web.method.annotation.ModelFactory.initModel(ModelFactory.java:115)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:753)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:967)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:869)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:85)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1521)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1478)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

Answer 1

I was able to solve this problem by specifying that the session should never time out. This is fine in our case since this app is secured behind a single sign on appl. Here is what I added to the application.properties file:
server.session-timeout=-1