Extending Classes - The Java Programming Language - page 158

perform a deeper clone whenever a shallow clone is not appropriatesuch
as in the IntegerStack example.
The object serialization mechanism (see page 549 ) allows you to write
entire object graphs to a stream of bytes and, using that generated
stream of bytes, create an equivalent copy of the original object graphs.
Serialization can provide a way to make deeper copies than those
provided by Object.clone .
Exercise 3.8 : Make Vehicle and PassengerVehicle into Cloneable types.
Which of the four described attitudes should each class take toward
cloning? Is the simple copying done by Object.clone correct for the clone
methods of these classes?
Exercise 3.9 : Write a Garage class whose objects can hold up to some
number of Vehicle objects in an array. Make Garage a Cloneable type, and
write a proper clone method for it. Write a Garage.main method to test it.
Exercise 3.10 : Make your LinkedList class (from the exercises in
Chapter 2 ) Cloneable , with clone returning a new list that refers to the
same values as the original list, not clones of the values. In other words,
changes to one list should not affect the other list, but changes to the
objects referenced by the list would be visible in both lists.