Example decorator pattern in Groovy using @DeleGate

decorator_pattern.groovy

class Person {
  String firstName
  String lastName
}

class PersonDecorator {
  private @Delegate Person person
  def fullName() { 
   "$firstName $lastName"
  }
}
def person = new Person(firstName: "Sean", lastName: "Brady")
def personDecorator = new PersonDecorator(person: person)

println personDecorator.fullName()