Java实现单链表基础操作

package linkedQueue;

public 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;
    }

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


}

package linkedQueue;


import java.util.Stack;

public class SingleLinkedList {
    private HeroNode head = new HeroNode(0, "", "");

    public HeroNode getHead() {
        return head;
    }

    //反向打印节点
    public static void reversePrint(HeroNode head) {
        if (head.next == null) {
            return;
        }
    //    创建一个栈
        Stack<HeroNode> heroNodes = new Stack<>();
        HeroNode cur = head.next;
        while (cur != null) {
            heroNodes.push(cur); //入栈
            cur = cur.next;
        }
    //    出栈打印
        while (heroNodes.size() > 0) {
            System.out.println(heroNodes.pop());
        }
    }

    /**
     * 添加节点
     * @param heroNode
     */
    public void add(HeroNode heroNode) {
        HeroNode temp = head;
        while (true) {
            if (temp.next == null) {
                break;
            }
            temp = temp.next;
        }
        temp.next = heroNode;
    }

    /**
     * 有序添加节点
     * @param herNode
     */
    public void addByOrder(HeroNode herNode) {
        HeroNode temp = head;
        boolean flag = false;
        while (true) {
            if (temp.next == null) {
                break;
            }
            if (temp.next.no > herNode.no) {
                break;
            } else if (temp.next.no==herNode.no) {
                flag = true;
                break;
            }
            temp = temp.next;
        }
        if (flag) {
            System.out.println("你要插入的节点的编号已经存在！！！！");
        } else {
            herNode.next = temp.next;
            temp.next = herNode;
        }
    }

    /**
     * 更新节点数据
     * @param newHeroNode
     */
    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) {
            //    找到
                flag = true;
                break;
            }
            temp = temp.next;
        }
        if (flag) {
            temp.name = newHeroNode.name;
            temp.nickname = newHeroNode.nickname;
        } else {
        //    没有找到
            System.out.println("没有找到编号" + newHeroNode.no + "的节点，不能修改");
        }

    }

    /**
     * 刪除节点
     * @param no
     */
    public void del(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;
        }

    }

    /**
     * 遍历节点
     */
    public void showList() {

        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;
        }

    }

    /**
     * 统计有效节点的个数
     */
    public static int getLength(HeroNode head) {
        if (head.next == null) { //空链表
            return 0;
        }
        int length = 0;
        HeroNode herNode = head.next;
        while (herNode != null) {
            length++; // 计数
            herNode=herNode.next; // 指针后移
        }
        return length;
    }

    /**
     * 求倒数第index个节点
     * @param head 头节点
     * @param index 倒数第k个
     * @return
     */
    public static HeroNode findLastIndexNode(HeroNode head, int index) {
        // 判断是否是空链表
        if (head.next == null) {
            return null;
        }

        // 拿到链表的长度
        int size = getLength(head);
        // index校验，看是否在范围内
        if (index <= 0 || index > size) {
            return null;
        }
        // 定位倒数第index个节点
        HeroNode herNode = head.next;
        for (int i = 0; i < size - index; i++) {
            herNode = herNode.next;
        }
        return herNode;

    }

    //单链表反转
    public static void reverseList(HeroNode head) {
    //    如果当前链表为空或者只有一个节点，直接返回
        if (head.next == null || head.next.next == null) {
            return;
        }

    //    定义辅助变量来遍历链表
        HeroNode cur = head.next;
        HeroNode next = null;//指向当前节点[cur]的下一个节点
        HeroNode reverseHead = new HeroNode(0, "", "");
    //    遍历原来节点，每遍历一个节点，将其取出，并放在新的链表的最前端
        while (cur != null) {
            next = cur.next;//暂时保存当前节点的下一个节点
            cur.next = reverseHead.next;//将cur的下一个节点指向新的链表的最前端
            reverseHead.next=cur;//将cur链接到新的链表
            cur = next;
        }
        head.next = reverseHead.next;

    }

}