Groovy @ symbol before fields

Question

What does @ means before a field name in Groovy? For some classes I am able to access private fields that are not directly accessible, let's take ComposedClosure for example:

public class Person {   private String name }  def u = new Person(name:"Ron") println u.@name //Ron println u.name //Ron  a = {2} >> {3} println a.@first //first closure object println a.first //runtime error 

Answer 1

It allows you to override groovy's use of property accessors. If you write:

println u.name 

groovy will invoke the automatically generated getter Person.getName(). If you write:

println u.@name 

it will go directly to the field like it would in Java. In the case of the closure, it seems to have a first field but not a corresponding getFirst accessor.

In the groovy manual, it's documented as the direct field access operator.