Java Reference
In-Depth Information
Display 15.14
A Generic Linked List with a Deep Copy
clone
Method
(part 2 of 3)
13
public
Node(T newData, Node<T> linkValue)
14 {
15 data = newData;
16 link = linkValue;
17 }
18 }
//End of Node<T> inner class
19
private
Node<T> head;
20
public
LinkedList( )
21 {
22 head =
null
;
23 }
24
/
**
25
Produces a new linked list, but it is not a true deep copy.
26 Throws a NullPointerException if other is null.
27
*
/
28
public
LinkedList(LinkedList<T> otherList)
29 {
30
if
(otherList ==
null
)
31
throw new
NullPointerException( );
32
if
(otherList.head ==
null
)
33 head =
null
;
34
else
35 head = copyOf(otherList.head);
36 }
37
38
public
LinkedList<T> clone( )
39 {
40
try
41 {
42 LinkedList<T> copy =
43 (LinkedList<T>)super.clone( );
44
if
(head ==
null
)
45 copy.head =
null
;
46
else
47 copy.head = copyOf(head);
48
return
copy;
49 }
50
catch
(CloneNotSupportedException e)
51 {
//This should not happen.
52
return null
;
//To keep the compiler happy.
53 }
54 }
55
/
*
56 Precondition: otherHead != null
57 Returns a reference to the head of a copy of the list
58 headed by otherHead. Returns a true deep copy.
59
*
/
60
private
Node<T> copyOf(Node<T> otherHead)
