java - 在链表中添加节点

Question

尝试在下面的程序中实现single-linked-list，我真的无法理解如何在链接列表中添加节点(首先，我尝试在空链接列表)。

简单来说，我尝试 setData 和 setNext 但 getSizeofList() 每次都返回 0 ....现在对我来说真的看起来像火箭科学!!

问题:有人可以告诉我如何实现它......或者更确切地说，向现有链表添加一个节点......

到目前为止我所尝试过的以及为什么它们不起作用:我引用了多个程序，但它们对我来说太复杂而无法理解(火箭科学)，所以写道下面的程序是我从算法中理解的……但即使在算法中，它们也只是展示了如何实现的方法，这就是我失败的地方，因为我不明白什么是数据类型和添加节点时要传递 value...

请注意，我不是java人，所以请放轻松，这个问题是为了学习而提出的

package Data_S;

public class Linked_List {

    private int data;
    private Linked_List next_ptr;
    private Linked_List headNode = null;

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub

        Linked_List ll = new Linked_List();
        //ll.setnext(25);
        ll.insert_node(24);
        ll.traverse();
        ll.getSizeofList();
    }


    //size of list
    public void getSizeofList()
    {
        int l = 0;
        Linked_List curr = headNode;
        while(curr != null)
        {
            l++;
            curr = curr.getnext();
        }
        System.out.print("Size of list is = "+l);
    }

    //insert node
    public void insert_node(/*Linked_List node, */int data)
    {
        if(headNode == null)
        {
            System.out.println("in insert"); // checking
            this.setnext(headNode);
            this.setData(data);
            System.out.print("value = "+this.getData());
        }
    }

   //set data for this node
    public void setData(int data)
    {
        this.data = data;
    }

    //return the data
    public int getData()
    {
        return this.data;
    }

    //set next pointer
    public void setnext(Linked_List next_ptr)
    {
        this.next_ptr = next_ptr;
    }

    //get next pointer
    public Linked_List getnext()
    {
        return this.next_ptr;
    }


}

Answer 1

您必须区分链表的单个链(节点)和整个容器(LinkedList)。

public class LinkedList {
    Node head;
    int size; // Maybe

    public void insertAtEnd(int data) {
        Node previous = null;
        for (Node current = head; current != null; current = current.next) {
            previous = current;
        }
        Node baby = new Node(data);
        if (previous == null) {
            head = baby;
        } else {
            previous.next = baby;
        }
        ++size;
    }

    public void insertInSortedList(int data) {
        Node previous = null;
        Node current = null;
        for (current = head; current != null && data < current.data;
                current = current.next) {
            previous = current;
        }
        Node baby = new Node(data);
        baby.next = current;
        if (previous == null) {
            head = baby;
        } else {
            previous.next = baby;
        }
        ++size;
    }
}

class Node {
    int data;
    Node next;
    Node(int data) {
        this.data = data;
    }
}

有时人们可能会将封装视为:

public class LinkedList {
    private static class Node {
    }
    ...
}