Sometimes you want to render directly to a known template from a controller.
To do this you can use the documented method
renderTemplate(String templateName, Object args)
Doing so requires that the first parameter be the complete path to the template.
But there is a shortcut that allows you to use the “@” symbol with the fully qualified class and method.
renderTemplate("@Registration.signup", user) or render("@Registration.signup", user)
which gets expanded to "Registration/signup.html".
And if the template exists in the same Controller you can omit the class and simply use the method name.
render("@signup", user) which is expanded to "Registration/signup.html" if called from the Registration controller.