Question

我在eclipse中使用java创建了一个简单的单链表程序。我创建了一个主类和2个类文件node.java和linkedlist.java，但是我无法实例化类型节点，但是我的节点类不是静态的。我不能实例化类型节点吗？

app.java
package linkedlist.singlelinkedlist;
This is my main class
/**
 * Hello world!
 *
 */
public class app 
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
        LinkedList list=new LinkedList();
        list.insert(10);
        list.insert(15);
        list.insert(20);
        list.show();

    }
}
node.java
This is my node class file
public class Node {
    int data;
    Node next;

}

linkedlist.java

这是我的LinkedList类文件

public class LinkedList {
    Node head;

    public void insert(int data)
    {
        Node node=new Node();#why cant i instantiate node?
        node.data=data;
        node.next=null;
        if(head==null)
        {
            head=node;
        }
        else
        {
            Node n=head;
            while(n.next!=null)
            {
                n=n.next;
            }
            n.next=node;
        }
    }
    public void show()
    {
        Node x=head;``
        while(x.next!=null)
        {
            System.out.println(x.data);
            x=x.next;
        }
        System.out.println(x.data);
    }

}


Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
    Cannot instantiate the type Node
    data cannot be resolved or is not a field
    next cannot be resolved or is not a field
    next cannot be resolved or is not a field
    next cannot be resolved or is not a field
    next cannot be resolved or is not a field

    at linkedlist.singlelinkedlist.LinkedList.insert(LinkedList.java:9)
    at linkedlist.singlelinkedlist.app.main(app.java:13)
Hello World!

如何实例化类型节点并纠正错误？

Answer 1

我刚刚编译了您的代码，它运行正常。

注意：LinkedList也是本机Java类。确保您的程序未指向本机类而不是类。

代码：

package me.PauMAVA.Tests;

public class Main 
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
        LinkedList list=new LinkedList();
        list.insert(10);
        list.insert(15);
        list.insert(20);
        list.show();

    }
}

package me.PauMAVA.Tests;

public class LinkedList {
    Node head;

    public void insert(int data)
    {
        Node node=new Node();
        node.data=data;
        node.next=null;
        if(head==null)
        {
            head=node;
        }
        else
        {
            Node n=head;
            while(n.next!=null)
            {
                n=n.next;
            }
            n.next=node;
        }
    }
    public void show()
    {
        Node x=head;
        while(x.next!=null)
        {
            System.out.println(x.data);
            x=x.next;
        }
        System.out.println(x.data);
    }

}

package me.PauMAVA.Tests;

public class Node {
    int data;
    Node next;

}

输出：

Hello World!
10
15
20

为什么我不能实例化类型节点？

1 个答案: