双向链表增删改查（有点问题顺序增加不到尾部）

package com.linkedlist;

import java.util.SortedMap;

/**
 * @Auther: 大哥的叔
 * @Date: 2019/7/29 05:07
 * @Description:
 */
public class DoubleLinkedListDemo {
    public static void main (String[] args) {
        HeroNode2 hero1 = new HeroNode2(1,"1","1");
        HeroNode2 hero2 = new HeroNode2(2,"2","2");
        HeroNode2 hero3 = new HeroNode2(3,"3","3");
        HeroNode2 hero4 = new HeroNode2(4,"4","4");
        HeroNode2 hero5 = new HeroNode2(5,"5","5");
        HeroNode2 hero6 = new HeroNode2(4,"6","6");

        DoubleLinkedList doubleLinkedList = new DoubleLinkedList();
        doubleLinkedList.add(hero2);
        doubleLinkedList.add(hero1);
        doubleLinkedList.add(hero3);
        doubleLinkedList.show();
        doubleLinkedList.addByorder(hero2);
        doubleLinkedList.show();
        doubleLinkedList.delete(2);
        doubleLinkedList.show();
        doubleLinkedList.update(hero6);
        doubleLinkedList.show();
    }
}

class DoubleLinkedList{
      private HeroNode2 head = new HeroNode2(0,"","");

      public HeroNode2 gethead(){
          return head;
      }
    //这种方式只能添加最后，而且没有判断依据如果重复添加一个会死循环
      public void add(HeroNode2 heroNode2){
          HeroNode2 temp = head;
          while (true){
              if (temp.next == null){
                  break;
              }
              //没有找到最后，temp后移
              temp = temp.next;
          }
          temp.next = heroNode2;
          heroNode2.pre = temp;
      }

      public void addByorder(HeroNode2 heroNode2){

          HeroNode2 temp = head.next;
          boolean flag = false;
          while (true){
              if(temp==null){
                  System.out.println("空");
                  break;
              }
              if(temp.next.no>heroNode2.no){//在编号内
                break;
              }else if (temp.next.no==heroNode2.no){
                  flag=true;
                  break;
              }
              temp =temp.next;
          }
          if (flag){
              System.out.println("已存在");
          } else {
              heroNode2.next = temp.next;
              temp.next= heroNode2;
         }
      }

      public void delete(int no){
        if (head.next==null){
            System.out.println("空");
            return;
        }
        HeroNode2 temp = head.next;
        boolean flag = false;
        while (true){
            if (temp==null){
               break;
            }
            if (temp.no==no){
                flag=true;
                break;
            }
            temp = temp.next;
        }
        if (flag){
            //temp前一个节点的后继节点指向temp的后继节点
            temp.pre.next = temp.next;
            if(temp.next != null){
                temp.next.pre = temp.pre;//后一个节点的前驱指向temp的前一个节点
            }
        }else {
            System.out.println("不存在");
        }

      }

      public void update(HeroNode2 newheroNode2){
          if (head.next ==null){
              System.out.println("空");
              return;
          }

          HeroNode2 temp = head.next;
          boolean flag = false;
          while (true){
              if (temp==null){
                  break;
              }
              if (temp.no==newheroNode2.no){
                  flag=true;
                  break;
              }
              temp = temp.next;
          }
          if (flag){
              temp.name = newheroNode2.name;
              temp.nickname = newheroNode2.nickname;
          }else {
              System.out.println("不存在");
          }
      }

      public void  show(){
          if (head.next==null){
              System.out.println("空");
              return;
          }
          HeroNode2 temp = head.next;
          while (true){
              if (temp==null){
                  System.out.println("遍历结束");
                  break;
              }
              System.out.println(temp);
              temp = temp.next;
          }

      }
}

class HeroNode2{
    public int no;
    public  String name;
    public String nickname;
    public HeroNode2 next;
    public HeroNode2 pre;

    public HeroNode2 (int no, String name, String nickname) {
        this.no = no;
        this.name = name;
        this.nickname = nickname;
    }

    @Override
    public String toString () {
        return "HeroNode2{" +
                "no=" + no +
                ", name='" + name + '\'' +
                ", nickname='" + nickname + '\'' +
                '}';
    }
}