Question

I am using grails 2.0.1 and overriding render method.

i have the following code.

 grailsApplication.controllerClasses.each { controller ->
          //keep old render method
          def original = controller.metaClass.getMetaMethod("render", [Map] as Class[])
          controller.metaClass.originalRender = original.getClosure()

          controller.metaClass.renderForBrand = { Map args ->  
          originalRender(args)   
           }
    }

In original.getClosure() i got the below Error.

Message: groovy.lang.MissingMethodException: No signature of method: org.codehaus.groovy.reflection.CachedMethod.getClosure() is applicable for argument types: () values: []
Possible solutions: getClass()
   Line | Method
->> 300 | evaluateEnvironmentSpecificBlock in grails.util.Environment
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|   293 | executeForEnvironment            in     ''
|   269 | executeForCurrentEnvironment . . in     ''
|   303 | innerRun                         in java.util.concurrent.FutureTask$Sync
|   138 | run . . . . . . . . . . . . . .  in java.util.concurrent.FutureTask
|   886 | runTask                          in java.util.concurrent.ThreadPoolExecutor$Worker
|   908 | run . . . . . . . . . . . . . .  in     ''
^   662 | run                              in java.lang.Thread

In grails 1.3.7 my code is working fine, In case of grails 2.x it fails.
Any help is greatly appriciated.
Thanks.

Answer 1

You might save a reference to the original render method and call the invoke method in order to execute it:

grailsApplication.controllerClasses.each { controller ->
          //keep old render method
          def originalRenderMethod = controller.metaClass.getMetaMethod("render", [Map] as Class[])
          controller.metaClass.renderForBrand = { Map args ->  
              originalRenderMethod.invoke(delegate, args)   
          }
}

This mechanism works regardless of using Grails 1.3.x or 2.0.x (I tested both).