双端链表的增加，删除，修改，遍历操作的实现

缺乏、安全感 2023-07-07 08:05 11阅读 0赞

package com.yg.linkedList;/*
    @author  GeQiLin
    @date    2020/2/21  13:46
    */
    
    public class DoubleLinkedListDemo {
        public static void main(String[] args) {
            //测试
            System.out.println("双向链表的测试");
            DoubleLinkedList doubleLinkedList = new DoubleLinkedList();
    //        doubleLinkedList.addNode(new HereNode2(1, "宋江", "及时雨"));
    //        doubleLinkedList.addNode(new HereNode2(3, "吴用", "智多星"));
    //        doubleLinkedList.addNode(new HereNode2(2, "卢俊义", "玉麒麟"));
    //        doubleLinkedList.addNode(new HereNode2(4, "林聪", "豹子头"));
            HereNode2 head = doubleLinkedList.getHead();
    //        DoubleLinkedList.showHereNode2(head);
    
            //删除双向链表
    //        doubleLinkedList.delNodeByNo(2);
    //        System.out.println("删除后***");
    //        DoubleLinkedList.showHereNode2(head);
    
            //修改节点信息
    //        doubleLinkedList.updataNode(new HereNode2(2, "haha", "heheh"));
    //        System.out.println("修改后***");
    //        DoubleLinkedList.showHereNode2(head);
    
            //测试按照编号添加节点
            doubleLinkedList.addNodeByNo(new HereNode2(1, "宋江", "及时雨"));
            doubleLinkedList.addNodeByNo(new HereNode2(3, "吴用", "智多星"));
            doubleLinkedList.addNodeByNo(new HereNode2(2, "卢俊义", "玉麒麟"));
            doubleLinkedList.addNodeByNo(new HereNode2(4, "林聪", "豹子头"));
            DoubleLinkedList.showHereNode2(head);
        }
    }
    
    class DoubleLinkedList {
        private HereNode2 head = new HereNode2(0, "", "");
    
        public HereNode2 getHead() {
            return head;
        }
    
        //显示节点(遍历)
        public static void showHereNode2(HereNode2 head) {
            if (head.next == null) {
                System.out.println("链表为空!!");
                return;
            }
            HereNode2 temp = head;
            while (true) {
    
                if (temp.next == null) {
                    return;
                }
                System.out.println(temp.next);
                temp = temp.next;
    
            }
        }
    
        //添加节点
        public void addNode(HereNode2 node) {
            if (node == null) {
                return;
            }
            HereNode2 temp = head;
            while (true) {
                if (temp.next == null) {
                    break;
                }
                temp = temp.next;
            }
            //形成一个双向链表
            temp.next = node;
            node.pre = temp;
    
        }
    
        //修改链表节点信息
        public void updataNode(HereNode2 newNode) {
            boolean flag = false;
            if (head.next == null) {
                System.out.println("列表为空!!");
                return;
            }
            HereNode2 temp = head.next;
            while (true) {
                if (temp == null) {
                    break;
                } else if (temp.no == newNode.no) {
                    flag = true;
                    break;
                }
                temp = temp.next;
            }
            if (flag) {
                temp.name = newNode.name;
                temp.nickName = newNode.nickName;
            } else {
                System.out.println("该节点不存在!!");
            }
        }
    
        //删除节点
        public void delNodeByNo(int no) {
            boolean falg = false;
            if (head.next == null) {
                System.out.println("节点为空!!");
                return;
            }
            HereNode2 temp = head;
            while (true) {
                if (temp == null) {
                    System.out.println("节点为空!!");
                    break;
                }
                if (temp.no == no) {
                    falg = true;
                    break;
                }
                temp = temp.next;
    
            }
            if (falg) {
                temp.pre.next = temp.next;
                //如果temp是最后一个节点会出现空指针异常
                if (temp.next != null) {
                    temp.next.pre = temp.pre;
                }
    
    
            } else {
                System.out.println("要删除的节点不存在!!");
            }
        }
    
        //按照编号顺序添加节点
        public void addNodeByNo(HereNode2 node) {
            if (node == null) {
                return;
            }
            boolean flag = false;
            HereNode2 temp = head;
            while (temp.next != null) {
                if (temp.next.no == node.no) {
                    flag = true;
                    break;
                } else if (temp.next.no > node.no) {
                    break;
                }
                temp = temp.next;
            }
            if (flag) {
                System.out.println("编号为" + temp.next.no + "的节点已经存在添加失败");
                return;
            }
            if(temp.next!=null){
                temp.next.pre=node;
                node.next=temp.next;
            }
            temp.next=node;
            node.pre=temp;
    
    
        }
    }
    
    class HereNode2 {
        public int no;
        public String name;
        public String nickName;
        public HereNode2 next;
        public HereNode2 pre;
    
        public HereNode2(int no, String name, String nickName) {
            this.no = no;
            this.name = name;
            this.nickName = nickName;
            this.next = next;
        }
    
        @Override
        public String toString() {
            return "HereNode{" +
                    "no=" + no +
                    ", name='" + name + '\'' +
                    ", nickName='" + nickName + '\'' +
                    '}';
        }
    }