如何从文件中读取并将内容保存到链表中

Question

我正试图为一个程序编写代码，该程序将txt文件的内容保存到一个单链表中，txt文件中的每一行都代表一个对象。我使用扫描器从文件中读取，但我不知道如何获得列表中的单词。

任何提示或提示都是非常感谢的。

my attempt:

class Item

public class Item implements Serializable {
private String name;
private double price;
public Item() {
name="" ; 
price=0.00 ;
}
public Item(String n, double p) {
name = n ; 
price = p ;
}
public void setName(String n) {
name = n ;
}
public void setPrice(double p) { price = p ;
}
public String getName() { 
return name ; 
}
public double getPrice() {
return price ;
}
}

class Node

public class Node {
public Item data ;
public Node next ;
public Node(Item d) {
    data = d ;
}
public Node(Item d, Node n) {
    data = d ; 
    next = n ; 
}
public String toString() {
    return data+"";
}
}

类listitem

public class ListItems {
private Node first;
public ListItems(){
    first=null;
}
public boolean isEmpty(){
    return first==null;
}
public void addAnItems(Item d, int i){
    Node node1=new Node(d);
    node1.next=first;
    first=items.get(i);
}
public void displayList(){
    Node current = first;
        while(current != null){
        System.out.println(current.toString());
        current=current.next;
        }
}
}

类FileItems

import java.io.* ;
import java.util.* ;
public class FileItems {
public static void main (String[]args){
Scanner input1=new Scanner(System.in) ;
        try {
        Scanner input2=new Scanner(new File("items.txt")) ;
        }
        catch (FileNotFoundException e) {
        System.out.println("ERROR OPENING FILE") ;
        System.Exit(1) ;
        }
        while (input2.hasNext()){
        String name1=input2.next() ;
        double price1=input2.nextDouble() ;
        }
            ListItems items=new ListItems();
                System.out.println("CHOOSE ONE OF THE FOLLOWING OPTIONS :") ;
                System.out.println("ENTER 1 TO ADD AN ITEM TO THE LIST") ;
                System.out.println("ENTER 2 TO DELETE AN ITEM FROM THE LIST") ;
                System.out.println("ENTER 3 TO DISPLAY ALL THE ITEMS IN THE LIST") ;
                System.out.println("ENTER 4 TO CLOSE THE PROGRAM") ;
                int in=input1.nextInt() ;
                        switch (in) {
                        case 1 : case1() ; 
                            break ;
                        case 2 : case1() ;
                            break ;
                        case 3 : displayList() ;
                            break ;
                        case 4 : System.Exit(1) ;
                            break ;
                        }
                        public void case1() {
                            System.out.println("ENTER THE NAME OF THE ITEM, THE PRICE AND THE INDEX ");
                            try {
                            System.out.println("NAME: ") ; 
                                String n2=input1.next() ; 
                            System.out.println("PRICE: ") ;
                                double p2=input1.nextDouble() ;
                            System.out.println("INDEX: ") ; 
                                int index=input1.nextInt() ;
                            }
                            catch (InputMismatchException e) {
                            System.out.print("INVALID INPUT") ;
                            }
                        Item I=new Item(n2, p2) ;
                        addAnItem(I, index) ;
                        }
                        public static case2() {
                            System.out.println("ENTER THE INDEX OF THE ITEM TO DELETE IT ") ;
                            try {
                            int index=input1.nextInt() ;
                            }
                            catch (InputMismatchException e) {
                            System.out.print("INVALID INPUT") ;
                            }
                        items.remove(index) ;
                        }
        }
        }

Answer 1

打开文本文件，以字符串形式读取每一行，并将该字符串对象放入LinkedList中。按倒序打印LinkedList中的所有行。

import java.util.*;
import java.io.*;
public class FileLinkList
{
public static void main(String args[])throws IOException{
String content = new String();
int count=1;
File file = new File("abc.txt");
LinkedList<String> list = new LinkedList<String>();
 try {
Scanner sc = new Scanner(new FileInputStream(file));
while (sc.hasNextLine()){
content = sc.nextLine();
list.add(content);
}
sc.close();
}catch(FileNotFoundException fnf){
fnf.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
System.out.println("nProgram terminated Safely...");
}
Collections.reverse(list);
Iterator i = list.iterator();
while (i.hasNext()) {
System.out.print("Node " + (count++) + " : ");
System.out.println(i.next());
}
 }
 }