CODEWITHSUNDEEP
grailsgroovyservice
Jithin
Jithin

Reputation: 1765

grails service inside a package


I'm pretty new to grails and spring
Me created a service like this 

services\com.mypackage\MyService

where 

class MyService {
    static transactional = true

    def serviceMethod(params) {
         println "params:"+params
    }
}

Then when in my controller 

controller\com.mypackage\mycontroller

Then in its action I tried to access like this 

def myaction= {
        com.mypackag.MyService myService //also used def myService
        myService.serviceMethod(params)
        render(view: "otherpage")
    }

But it show the following error :(

java.lang.NullPointerException: Cannot invoke method serviceMethod() on null object

it cannot make the object of myservice. 

myService shows null

What mistake i have done?

It will be very helpful if anyone provide me some good simple links and tutorials for using service with grails
Thank you

Upvotes: 1

Views: 1313

Answers (3)

Labeeb Panampullan
Labeeb Panampullan

Reputation: 34823

One mistake you have done.
You are declaring that myService inside your myaction closures. Where it should be done in the controller outside any of your methods or closures.
You can access your service methods using your service object (here myService) inside any of your methods or closures

So change like this
In your controller\com.mypackage\mycontroller declare your service first 

def myService

Then you can access it in any closures 

 def myaction= {
        myService.serviceMethod(params)
        render(view: "otherpage")
    }

Upvotes: 4

Dónal
Dónal

Reputation: 187499

Your directory hierarchy does not correspond to you packages. You should change the directory hierarchy for your service to:

services\com\mypackage\MyService.groovy

and make sure you add the following at the top of MyService.groovy

package com.mypackage

class MyService {
  // .....
}

Similarly, change the directory hierarchy for your controller to

controller\com\mypackage\MyController.groovy

Then to get a reference to your service inside your controller

// add the correct package statement
package com.mypackage

// rename the controller and the mycontroller.groovy file to MyController
class MyController {

  // this will be injected by Spring (it must be named with a lower-case 'm')
  def myService

  def myaction= {
    // use the service inside your action
    myService.serviceMethod(params)
    render(view: "otherpage")
  }
}

Upvotes: 1

tim_yates
tim_yates

Reputation: 171084

1) I'd read the Grails User guide on Services

2) I'd make your services using the command line tools grails provides as it will save you putting things in invalid directories (com.mypackage as a folder name is going to give you nothing but trouble), and it will make sure you have the correct package declarations at the top of your groovy files

Upvotes: 0

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