Grails Webflow errors on first access

Question

I've developed a simple webflow in Grails (mostly to experiment with using webflows- its a bit overkill for this case). After some trials and tribulations with Serializable objects, I have it working - sometimes.

Here's the rub- the first time I access the webflow after starting the app (run-app), I get this exception:

2010-06-16 09:11:25,580 [http-8080-3] [ERROR] [org.codehaus.groovy.grails.web.errors.GrailsExceptionResolver] No signature of method: groovy.lang.MissingMethodException.to() is applicable for argument types: (java.lang.String) values: [validate]
Possible solutions: is(java.lang.Object), any(), use([Ljava.lang.Object;), getAt(java.lang.String), with(groovy.lang.Closure), any(groovy.lang.Closure)
groovy.lang.MissingMethodException: No signature of method: groovy.lang.MissingMethodException.to() is applicable for argument types: (java.lang.String) values: [validate]
Possible solutions: is(java.lang.Object), any(), use([Ljava.lang.Object;), getAt(java.lang.String), with(groovy.lang.Closure), any(groovy.lang.Closure)
        at com.sbs.component.survey.SurveyDefinitionController.invokeMethod(SurveyDefinitionController.groovy)
        at com.sbs.component.survey.SurveyDefinitionController$_closure3.doCall(SurveyDefinitionController.groovy:23)

If I "touch" the controller (make any edit, even if just adding a white-space) and then save the file, the webflow starts to work... it seems something is not getting wired up until the controller reloads at least once. Obviously this is a non-starter... any ideas what's causing this?

I'm using Grails 1.3.1 on Mac OSX Java 1.6.

Here's the skeleton of the webflow:

def createSurveyFlow = {
        select {

            }.to("validate")
            on("cancel").to("finish")
        }

        validate {
            on("approve") {

            }.to("finish")
            on("disapprove").to("select")
            on("cancel").to("finish")
        }

        finish {
            action {
                flash.message = "SurveyDefinition created"            
            }
            redirect(controller:"surveyDefinition", action:"index")
        }

    }

Answer 1

I may have figured it out- it seems out that webflow definitions and controller actions don't much like being on the same controller. When I moved the webflow to it's own controller, this (and other) issues seemed to go away. For now, at least. I'll report back if/when I learn more.