Java数据结构之双向链表

package JavaProject;public class TestDuLinkList {public static void main(String[] args) {// TODO Auto-generated method stubDuLinkList<String> list = new DuLinkList<String>();list.insert("aaaa" , 0);System.out.println("插入aaaa：");list.traverse();list.addTail("bbbb");System.out.println("尾插法插入bbbb：");list.traverse();list.insert("cccc" , 0);System.out.println("插入cccc：");list.traverse();list.insert("dddd" , 1);System.out.println("插入dddd：");list.traverse();//删除索引为2处的元素list.delete(2);System.out.println("删除索引为2的元素");list.traverse();//获取cccc字符串在顺序线性表中的位置System.out.println("cccc在顺序线性表中的位置：" + list.getIndex("cccc"));System.out.println("链表中索引1处的元素：" + list.getNode(1).data);list.delete(0);//删除链表第一个元素System.out.println("调用delete(0)后的链表:" );list.traverse();}}class DuLinkList<T>{class Node{public T data;public Node pre;public Node next;public Node(T data,Node pre,Node next){this.data = data;this.pre = pre;this.next = next;}}private Node header;private Node tail;private int size;public DuLinkList(){header = null;tail = null;}public int length(){return size;}public Node getNode(int index){if(index < 0 || index > size - 1){System.out.println("位置非法");}if(index <= size / 2){Node tempNode = header;for(int i=0;i<=size/2&&tempNode != null;tempNode=tempNode.next,i++){if(i == index){return tempNode;}}}else{Node tempNode = tail;for(int i=size-1;i>size/2&&tempNode!=null;tempNode=tempNode.pre,i--){if(i == index){return tempNode;}}}return null;}public int getIndex(T element){Node tempNode = header;if(tempNode != null){for(int i=0;i<size;i++){if(tempNode.data.equals(element)){return i;}tempNode = tempNode.next;}}return -1;}public void addTail(T element){if(header == null){header = new Node(element,null,null);tail = header;}else{Node tempNode = new Node(element,tail,null);tail.next = tempNode;tail = tempNode;}size++;}public void addHead(T element){if(tail == null){tail = new Node(element,null,null);header = tail;}else{Node tempNode = new Node(element,null,header);header = tempNode;}size++;}public void insert(T element,int index){if(index < 0 || index > size){System.out.println("位置非法");}if(header == null){addTail(element);}else{if(index == 0){addHead(element);}else{Node Pre = getNode(index - 1);Node newNode = new Node(element,Pre,Pre.next);Pre.next = newNode;newNode.next.pre = newNode;size++;}}}public T delete(int index){if(index < 0 || index > size -1){System.out.println("位置非法");}Node del = null;if(index == 0){del = header;header = header.next;header.pre = null;}else{Node Pre = getNode(index - 1);del = Pre.next;Pre.next = del.next;if(del.next != null){del.next.pre = Pre;}del.next = null;del.pre = null;}size--;return del.data;}public boolean empty(){return size == 0;}public void clear(){header = null;tail = null;size = 0;}public void traverse(){for(Node tempNode=header;tempNode!=null;tempNode=tempNode.next){System.out.printf("%s ",tempNode.data.toString());}System.out.println();}}