一、单链表定义

package com.sy.lineTable;

public class ListNode {
    public Integer value;
    public ListNode next;

    public ListNode(Integer value) {
        this.value = value;
    }
}

二、单链表基本操作

package com.sy.lineTable;

public class MyList {
    /**
     * 头结点的插入
     */
    public static void headInsert(ListNode head,ListNode newHead){
        newHead.next = head;
    }

    /**
     * 尾节点的插入
     */
    public static void tailInsert(ListNode tail, ListNode newTail){
        tail.next = newTail;
        newTail.next = null;
    }

    /**
     * 遍历
     */
    public static void traverse(ListNode head){
        while(head != null){
            System.out.print(head.value + " ");
            head = head.next;
        }
        System.out.println();
    }

    /**
     * 查找:返回索引
     */
    public static int find(ListNode head,Integer value){
        Integer index = -1;
        Integer count = 0;
        while(head != null){
            if(head.value == value){
                index = count;
                break;
            }
            head = head.next;

            count++;
        }
        return index;
    }

    /**
     * 插入
     * @param currentNode
     * @param needInsertNode
     */
    public static void insert(ListNode currentNode, ListNode needInsertNode){
        needInsertNode.next = currentNode.next;
        currentNode.next = needInsertNode;
    }

    /**
     * 删除
     * @param needDeleteNode
     */
    public static void delete(ListNode headNode, ListNode needDeleteNode){
        //尾节点的删除
        if(needDeleteNode.next == null){
            while(headNode != null){
                if(headNode.next == needDeleteNode){
                    headNode.next = null;
                    return;
                }
                headNode = headNode.next;
            }
        }

        //中间节点和头结点的删除:将下一个节点内容复制给删除节点,并删除下一个节点
        needDeleteNode.value = needDeleteNode.next.value;
        needDeleteNode.next = needDeleteNode.next.next;
    }

    public static void main(String[] args) {
        ListNode node1 = new ListNode(1);
        ListNode node2 = new ListNode(2);
        ListNode node3 = new ListNode(3);
        node1.next = node2;
        node2.next = node3;

        //遍历
        traverse(node1);//1 2 3

        //头结点插入
        ListNode newHead = new ListNode(0);
        headInsert(node1, newHead);
        traverse(newHead);//0 1 2 3

        //尾节点插入
        ListNode tailNode = new ListNode(4);
        tailInsert(node3, tailNode);
        traverse(newHead);//0 1 2 3 4

        //中间插入
        ListNode middleNode = new ListNode(6);
        insert(node2, middleNode);
        traverse(newHead);//0 1 2 6 3 4

        //删除
        delete(newHead, middleNode);
        traverse(newHead);//0 1 2 3 4

        //尾节点的删除
        delete(newHead, tailNode);
        traverse(newHead);//0 1 2 3
    }
}