Linked lists - Data Structures and Problem Solving Using Java - page 639

1 /**
2 * Adds an item to this collection, at the end.
3 * @param x any object.
4 * @return true.
5 */
6 public boolean add( AnyType x )
7 {
8 addLast( x );
9 return true;
10 }
11
12 /**
13 * Adds an item to this collection, at the front.
14 * Other items are slid one position higher.
15 * @param x any object.
16 */
17 public void addFirst( AnyType x )
18 {
19 add( 0, x );
20 }
21
22 /**
23 * Adds an item to this collection, at the end.
24 * @param x any object.
25 */
26 public void addLast( AnyType x )
27 {
28 add( size( ), x );
29 }
30
31 /**
32 * Adds an item to this collection, at a specified position.
33 * Items at or after that position are slid one position higher.
34 * @param x any object.
35 * @param idx position to add at.
36 * @throws IndexOutOfBoundsException if idx is not
37 * between 0 and size(), inclusive.
38 */
39 public void add( int idx, AnyType x )
40 {
41 Node<AnyType> p = getNode( idx, 0, size);
42 Node<AnyType> newNode = new Node<AnyType>( x, p.prev, p );
43 newNode.prev.next = newNode;
44 p.prev = newNode;
45 theSize++;
46 modCount++;
47 }

figure 17.24
add methods for
standard LinkedList
class

the node at index idx . In order for this to be suitable for addLast , getNode will
start its search from the end closest to the target node.