GRAILS Injecting services or classes into groovy source

Assuming you have below service class in your grails service(grails-app/services) directory.

class MyService {    
   def printSomething() {
     println "Hello World!!!"
   }
}

And we also have a groovy class under the src(src/groovy) directory and we wanted to inject MyService in this class like below.

class HelloWorld {
  MyService myService

  def printHelloWorld() {
     myService.printSomething();
  }
}  

Finally, we put our injection logic in resources.groovy(grails-app/conf/spring/resources.groovy)

import package.HelloWorld

beans = {
helloWorld(HelloWorld) {
        myService = ref("myService")
    }
}