分为双向链表和单向链表

单向链表

分为带头结点和不带头结点的

带头结点的单向链表注意事项

1）元素的地址并非连续
2）没有被引用的节点会被垃圾回收
3）最后一个节点的下一个节点指向空
4）即便链表为空，也会初始化一个头结点

//带头结点的单向链表代码实现
public class SingleLinkedListDemo {
    public static void main(String[] args) {
        SingleLinkedList.HeroNode node1 = new SingleLinkedList.HeroNode(1,"曹操1","到1");
        SingleLinkedList.HeroNode node2 = new SingleLinkedList.HeroNode(2,"曹操2","到2");
        SingleLinkedList.HeroNode node3 = new SingleLinkedList.HeroNode(3,"曹操3","到3");
        SingleLinkedList.HeroNode node4 = new SingleLinkedList.HeroNode(4,"曹操4","到4");
        SingleLinkedList.HeroNode node5 = new SingleLinkedList.HeroNode(5,"曹操5","到5");
        SingleLinkedList.HeroNode newNode = new SingleLinkedList.HeroNode(4,"曹操666","到666");
        SingleLinkedList list = new SingleLinkedList();
        list.add(node1);
        list.add(node2);
        list.add(node3);
        list.add(node4);
//        list.addByOrder(node1);
        list.set(newNode);
        list.remove(366);
        System.out.println(list);
    }
}
class SingleLinkedList{
    private HeroNode head = new HeroNode(0,"","");
    //添加元素/节点
    public void add(HeroNode heroNode){
        HeroNode temp = head;
        while (true){
            //当下一个节点为空表示该节点为最后一个节点
            if(temp.next == null){
                break;
            }
            //将当前节点指向下一个节点
            temp = temp.next;
        }
        //最后一个节点的下一个节点为要添加的元素
        temp.next = heroNode;
    }
    //根据编号顺序进行添加，如果编号已存在，则显示已存在
    public void addByOrder(HeroNode heroNode){
        HeroNode temp = head;
        while(true){
            if(temp.next == null){
                break;
            }else if(temp.next.no>heroNode.no) {
                break;
            }else if (temp.next.no == heroNode.no){
                System.out.println("addByOrder()编号已存在");
                return;
            }
            temp = temp.next;
        }
        heroNode.next = temp.next;
        temp.next = heroNode;
    }
    //更新节点
    public void set(HeroNode newNode){
        HeroNode temp = head;
        while(true){
            temp = temp.next;
            if (temp == null){
                System.out.println("set()未找到该节点");
                return;
            }
            if (temp.no == newNode.no){
                temp.name = newNode.name;
                temp.nickname = newNode.nickname;
                return;
            }
        }
    }
    //删除节点
    public void remove(int no){
        HeroNode temp = head;
        while (true){
            if (temp.next == null){
                System.out.println("remove()未找到该编号");
                return;
            }
            if (temp.next.no == no){
                temp.next = temp.next.next;
                return;
            }
            temp = temp.next;
        }
    }
    //显示列表内容（遍历）
    public String toString(){
        if (head.next == null){
            return "toString()链表为空";
        }
        HeroNode temp = head.next;
        while (true){
            if (temp == null){
                break;
            }
            System.out.println(temp);
            temp = temp.next;
        }
        return "";
    }
    //定义节点
    static class HeroNode{
        int no;
        String name;
        String nickname;
        HeroNode next;
        public HeroNode(int no,String name,String nickname){
            this.no = no;
            this.name = name;
            this.nickname = nickname;
        }
        @Override
        public String toString() {
            return "HeroNode{" +
                    "no=" + no +
                    ", name='" + name + '\'' +
                    ", nickname='" + nickname + '\'' +
                    '}';
        }
    }
}