简单_单链表

package sunfa;import java.util.Iterator;/** * 单链表 *  * @author Administrator *  */public class SingleLinkedList {public static void main(String[] args) {SingleLinkedList link = new SingleLinkedList();for (int i = 10; i < 20; i++) {link.add(i);}System.out.println("list:");Iterator it = link.iterator();while (it.hasNext()) {System.out.println(it.next());}System.out.println("getFirst:" + link.getFirst());System.out.println("getLast:" + link.getLast());link.remove(13);link.remove(17);System.out.println("删除后");it = link.iterator();while (it.hasNext()) {System.out.println(it.next());}}private Node head = new Node(null, null);private Node tail = null;public SingleLinkedList() {head.next = tail;}public Object getFirst() {if (head.next != null)return head.next.element;return null;}public Object getLast() {if (tail == null) {return null;}return tail.getElement();}public void add(Object o) {Node node = new Node(o, null);if (tail == null)head.next = node;elsetail.next = node;tail = node;}public Object remove(Object o) {for (Node e = head.next; e != head;) {Node current = e;e = e.next;if (e.element == o) {current.next = e.next;return e.element;}}return null;}// public Object find(int index){// if(tail==null){// return null;// }// while(index!=head.next.o){//// }// }public Iterator iterator() {return new Itr(head);}private static class Node {Object element;Node next;public Node(Object o, Node next) {super();this.element = o;this.next = next;}public Object getElement() {return element;}}private class Itr implements Iterator {private Node cur;public Itr(Node cur) {super();this.cur = cur;}public boolean hasNext() {return cur.next != null;}public Object next() {Object o = cur.next.element;cur = cur.next;return o;}public void remove() {}}}