Using safe method names in 'beforeInterceptor' interceptor in Grails 2.x

safe-method-name-in-before-interceptor.groovy

class MyController {

  /**
  * Normally, String type method name in except part of beforeInterceptor is legal. For example:
  * 
  * def beforeInterceptor = [action: this.&intercept, except: ['index', 'hede', 'hodo']]
  * 
  * But this is not safe for future naming refactorings. Instead, using closure-maker 
  * ampersand operator(.&) before method name and then getting 'method' property to get 
  * method name as String is better for future safe changes.
  */
  def beforeInterceptor = [action: this.&intercept, except: [this.&index.getProperty('method'),
                                                             this.&hede.getProperty('method'),
                                                             this.&hodo.getProperty('method')]]
  
  def index() {
    render "Exceptional endpoint, I am in index."
  }
  
  def hede() {
    render "Exceptional endpoint, I am in hede."
  }
  
  def hodo() {
    render "Exceptional endpoint, I am in hodo."
  }
  
  def helehele() {
    render "Enters intercept method before coming here. Hele Hele Hele is here!.."
  }
  
  private boolean intercept() {
    // Enters here before request handler method invocation and returns boolean true 
    // if the method is wanted to be called properly. Otherwise returns false.
    return true
  }
}