Java 链表的比较对象

Question

public class Node<E> {
    private E data;
    private Node<E> next;
    public Node<E>(){
        next = null;
    }
    public Node(E dataIn){
    data = dataIn;
    }       
}

///

class LinkedList<E>{
    public void insert(E dataIn){
            if(ctr != 0){
                Node<E> temp = new Node<E>(dataIn);
                Node<E> cursor = head;
                Node<E> prev = cursor;
                while(cursor != null && cursor.data.compareTo(dataIn) < 0){
                        prev = cursor;
                        cursor = cursor.next;
                }
                prev.next = temp;
                temp.next = cursor;
             }
             else
                add(dataIn);
             ++ctr;  
   }
}

在我的插入函数中，如何让 Java 知道 cursor.data 与 dataIn 的类型相同？（假设它们都是整数）抱歉，我为这个愚蠢的问题道歉。我是菜鸟，我不知道在哪里写 'compareTo' 函数，因为我使用的是 Integer ，而不是自定义数据类型。所以，当我编译代码时，我得到这个错误

required: E#1
found: no arguments
reason: actual and formal argument lists differ in length
where E#1,E#2 are type-variables:
E#1 extends Object declared in class LinkedList
E#2 extends Object declared in class Node
LinkedList.java:34: error: cannot find symbol
        while(cursor != null && cursor.data.compareTo(dataIn) < 0){
                                           ^
symbol:   method compareTo(E#1)
location: variable data of type E#2
where E#1,E#2 are type-variables:
E#1 extends Object declared in class LinkedList
E#2 extends Object declared in class Node

提前感谢您的关注！

Answer 1

按以下方式定义列表class

public class LinkedList<E extends Comparable<E>> {

    private static class Node<E> {

并确保 Node class 是嵌套静态的（在这种情况下可以是 private、package-private）。之后就可以将实现 Comparable 的任何类型添加到链表中。

Java 链表的比较对象

Java compareTo for LinkedList

java

linked-list

comparable