双链表

图示：

代码：

import lombok.Data;

public class DoubleLinkedListTest {
    public static void main(String[] args) {
        DoubleNode node1 = new DoubleNode(1, "吕布");
        DoubleNode node2 = new DoubleNode(2, "典韦");
        DoubleNode node3 = new DoubleNode(3, "赵云");
        DoubleNode node4 = new DoubleNode(4, "关羽");
        DoubleLinkedList doubleLinkedList = new DoubleLinkedList();
//        doubleLinkedList.tailInsert(node1);
//        doubleLinkedList.tailInsert(node4);
//        doubleLinkedList.tailInsert(node2);
//        doubleLinkedList.tailInsert(node3);
        doubleLinkedList.orderInsert(node1);
        doubleLinkedList.orderInsert(node4);
        doubleLinkedList.orderInsert(node2);
        doubleLinkedList.orderInsert(node3);
        doubleLinkedList.ascList();
        System.out.println("~~~~~~");
//        doubleLinkedList.descList();
        DoubleNode node5 = new DoubleNode(0, "张飞");
        doubleLinkedList.updateByNo(node5);
        doubleLinkedList.ascList();
//        doubleLinkedList.delByNo(5);
//        doubleLinkedList.ascList();

    }
}

@Data
class DoubleNode {
    /**
     * 编号
     */
    private int no;

    /**
     * 名称
     */
    private String name;

    private DoubleNode prev;
    private DoubleNode next;

    public DoubleNode() {

    }

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

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

class DoubleLinkedList {
    private DoubleNode headNode;

    public DoubleLinkedList() {
        headNode = new DoubleNode();
    }

    /**
     * 尾部添加节点
     * @param newNode
     * @return
     */
    public boolean tailInsert(DoubleNode newNode) {
        DoubleNode temp = headNode;
        while (temp.getNext() != null) {
            temp = temp.getNext();
        }
        temp.setNext(newNode);
        newNode.setPrev(temp);
        return true;
    }

    /**
     * 按编号顺序插入
     * @param newNode
     * @return
     */
    public boolean orderInsert(DoubleNode newNode) {
        DoubleNode temp = headNode;
        while (temp.getNext() != null) {
            if (temp.getNext().getNo() == newNode.getNo()) {
                System.out.println("已存在编号相同的节点，无法插入");
                return false;
            }
            if (temp.getNext().getNo() > newNode.getNo()) {
                newNode.setNext(temp.getNext());
                newNode.setPrev(temp);
                temp.getNext().setPrev(newNode);
                temp.setNext(newNode);
                return true;
            }
            temp = temp.getNext();
        }
        //遍历到最后没有找到比newNode的编号大的，插在最后面
        temp.setNext(newNode);
        newNode.setPrev(temp);
        return true;
    }

    /**
     * 正序遍历
     */
    public void ascList() {
        DoubleNode temp = headNode;
        while (temp.getNext() != null) {
            System.out.println(temp.getNext());
            temp = temp.getNext();
        }
    }

    /**
     * 倒序遍历
     */
    public void descList() {
        DoubleNode temp = headNode;
        while (temp.getNext() != null) {
            temp = temp.getNext();
        }

        while (true) {
            System.out.println(temp);
            if (temp.getPrev() == headNode) {
                break;
            }
            temp = temp.getPrev();
        }
    }

    /**
     * 根据编号修改节点
     * @param newNode
     * @return
     */
    public boolean updateByNo(DoubleNode newNode) {
        DoubleNode temp = headNode.getNext();
        while (temp != null) {
            if (temp.getNo() == newNode.getNo()) {
                temp.setName(newNode.getName());
                return true;
            }
            temp = temp.getNext();
        }
        System.out.println("未找到需修改的节点");
        return false;
    }

    /**
     * 根据编号删除节点
     * @param no
     * @return
     */
    public boolean delByNo(int no) {
        DoubleNode temp = headNode.getNext();
        while (temp != null) {
            if (temp.getNo() == no) {
                temp.getPrev().setNext(temp.getNext());
                if (temp.getNext() != null) {
                    temp.getNext().setPrev(temp.getPrev());
                }
                return true;
            }
            temp = temp.getNext();
        }
        System.out.println("未找到需删除的节点");
        return false;
    }
}