Grails get Session and Management in Service class

session grails service nullpointerexception httpsession
grailsInvas0r picture grailsInvas0r · Aug 15, 2011 · Viewed 25.6k times · Source

I have a problem with Grails Session. I was thinking about having a Service Class for my session handling. So I created a class called "SessionService" (under grails-app/services/grails/). 

class SessionService {
    static transactional = true
    GrailsWebRequest request = RequestContextHolder.currentRequestAttributes()
    GrailsHttpSession session = request.session

    def setTestvar(String value) {
        if (session != null)
            session.setAttribute("sTeststring", value)
    }

    def getTestvar() {
        if (session != null)
            session.getAttribute("sTeststring")
    }
}

The Problem is now, that I get a Nullpointer-Exception: "Method threw 'java.lang.NullPointerException' exception. Cannot evaluate org.codehaus.groovy.grails.web.servlet.mvc.GrailsHttpSession.ToString()".

Usage of my Service Class e.g. in a Controller:

class SampleController {

    SessionService sessionService

    def selectAnything = {

        sessionService.setTestvar("test-value")
        render(view: "testview")
    }
}

What am I'm doing wrong here? Is it the right way? Or do I have to set "session = request.session" in every method?

Hope to get help from you.

Thank you very much in advance.

Cheers,

Marco

Answer

user852518 picture user852518 · Aug 15, 2011

where does RequestContextHolder come from? Its not visible in grails 3.3.8 (in plugin at least)

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