Groovy - Clone - Shallow Copy

import groovy.transform.AutoClone 
// Do not clone the teacher property.
@AutoClone(excludes = ['teacher'])
class Course {
    String name
    Date date
    Teacher teacher
}
 
@AutoClone()
class Teacher {
    String name
}
 
def mrhaki =
    new Teacher(name: 'mrhaki')
     
def course =
    new Course(
        name: 'Groovy 101',
        date: new Date() + 10,
        teacher: mrhaki)
 
// We make a deep copy.
def secondCourse = course.clone()
assert secondCourse != course
assert !secondCourse.is(course)
// Only the teacher property is
// a shallow copy.
assert secondCourse.teacher == mrhaki
assert secondCourse.teacher.is(mrhaki)
 
// Change property on teacher property on cloned instance.
secondCourse.teacher.name = 'hubert1'
 
assert secondCourse.teacher.name == 'hubert1'
assert course.teacher.name == 'hubert1'

println "secondCourse.teacher >>> " +secondCourse.teacher.name
println  "course.teacher >>> " +course.teacher.name
 
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