单链表的实现

链表（LinkedList）

1.链表是以节点的方式存储，是链式存储；
2.每个节点包含data域和next域；
3.链表的各个节点不一定是连续存储的；
4.链表分带头节点的链表和没有头节点的链表

链表在内存中的存储示意图

链表逻辑图

单链表的增删改查的实现

代码如下：

package com.company;

public class SingleLinkedListDemo {

    public static void main(String[] args) {
	// write your code here
        HeroNode hero1 = new HeroNode(1,"奈文摩尔","影魔");
        HeroNode hero2 = new HeroNode(2,"力丸","隐刺");
        HeroNode hero3 = new HeroNode(3,"卡尔","祈求者");
        HeroNode hero4 = new HeroNode(4,"昆卡","船长");
        SingleLinkedList list = new SingleLinkedList();
        /*list.add(hero1);
        list.add(hero2);
        list.add(hero3);
        list.add(hero4);*/
        list.addByOrder(hero1);
        list.addByOrder(hero3);
        list.addByOrder(hero2);
        list.addByOrder(hero4);

        list.list();
        HeroNode newHeroNode = new HeroNode(2,"莉娜","火女");
        list.update(newHeroNode);

        System.out.println("修改后的链表~~~");
        list.list();

        list.delete(1);
        list.delete(4);
        System.out.println("删除后的列表");
        list.list();
    }
}

//定义SingleLinkedList管理英雄
class SingleLinkedList{
    //先初始化一个头节点，头节点不要动，不存放具体的数据
    private HeroNode head = new HeroNode(0,"","");
    public void add(HeroNode  heroNode){
        HeroNode temp = head;
        while (true){
            if(temp.next==null){
                break;
            }
            temp=temp.next;
        }
        temp.next=heroNode;
    }

    public void list(){
        if(head.next==null){
            System.out.println("链表为空");
            return;
        }
        HeroNode temp = head.next;
        while (true){
            if(temp==null){
                break;
            }
            System.out.println(temp);
            temp=temp.next;
        }
    }


    public void addByOrder(HeroNode heroNode){
        HeroNode temp = head;
        boolean flag = false;//标志添加的编号是否存在，默认为false
        while(true){
            if(temp.next==null){//说明temp已经在链表的最后
                break;
            }
            if(temp.next.no>heroNode.no){//位置找到，在temp后面
                break;
            }else if(temp.next.no==heroNode.no){//说明希望添加的heroNode已经存在
                flag = true;
                break;
            }
            temp = temp.next;
        }
        if(flag){
            System.out.printf("准备插入的英雄编号%d已经存在，不能加入",heroNode.no);
        }else {
            heroNode.next = temp.next;
            temp.next = heroNode;
        }
    }
    public void update(HeroNode newHeroNode){
        if(head.next == null){
            System.out.println("链表为空~");
            return;
        }
        HeroNode temp = head.next;
        boolean flag = false;
        while (true){
            if(temp==null){
                break;
            }
            if(temp.no==newHeroNode.no){
                flag = true;
                break;
            }
            temp = temp.next;
        }
        if(flag){
            temp.name = newHeroNode.name;
            temp.nickname = newHeroNode.nickname;
        }else {
            System.out.println("没有对应的英雄");
        }
    }
    public void delete(int no){
       HeroNode temp = head;
       boolean flag = false;
       while (true){
           if(temp.next==null){
               break;
           }
           if(temp.next.no==no){
               flag  = true;
               break;
           }
           temp=temp.next;
       }
       if(flag){
           temp.next = temp.next.next;
       }else {
           System.out.println("没有找到相应的节点");
       }
    }
}

//定义HeroNode，每个HeroNode对象就是一个节点
class HeroNode{
    public int no;
    public  String name;
    public String nickname;
    public HeroNode next;//指向下一个节点

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

    public String toString(){
        return "HeroNode[no="+no+",name = "+name+",nickname = "+nickname+"]";
    }
}