Groovy 1.7改变了“最终”？

class GCar2 {
  final miles = 0

  def getMiles() {
    println "getMiles called"
    miles
  }

  def drive(dist) {
    if (dist > 0) {
      miles += dist
    }
  }
}

def car = new GCar2()

println "Miles: $car.miles"
println 'Driving'
car.drive(10)
println "Miles: $car.miles"

try {
  print 'Can I see the miles? '
  car.miles = 12
} catch (groovy.lang.ReadOnlyPropertyException eX) {
  println ex.message

GroovyCar2.groovy: 20: cAnnnot access final field or property outside of constructor.
 @ line 20,column 35.
     def drive(dist) { if (dist > 0) miles += dist }
                                     ^

1.7之前的Groovy版本不会出错.我查看了我能找到的任何文档,但没有看到讨论的问题.这里发生了什么？

亚伦