text file to linked list objects java-CodePudding

How can I make a linked list from a file? I have a file and each line is an object with its width height and length so the file is a 2d array. I am trying to make a linked list of objects but with just the variable next in the object class and no node class or linked list class also I can't use any arrays besides the split one. Since there are 7 objects a linked list of 7 nodes should be returned. I have done this so far which is similar to making array to linked list but I don't think it's correct

file:
2 18 9
1.2 6.32 9.2
2.0 2.0 2.0
5.0 1.4 7.0
121.0 107.0 12.0
4.2 4.2 4.2
8.0 1.0 11.0

//main
  static Box LinkedList(String file){
   file = "ll.txt";
   Scanner scan = new Scanner(file);
   while (scan.hasNextLine()){
         String line = scan.nextLine();
          String [] arr = line.split(" ");
          Box b = new Box(Double.parseDouble(arr[0]),Double.parseDouble(arr[1]), Double.parseDouble(arr[2]));

          Box head = arr[0];
          Box temp = head;
         for (int i = 0; i < row; i  ){
             Box s = arr[i];
             temp.next = s;
             temp = temp.next; 
         }
   
  }
  return head;
 }

 //class
  class Box{
    private double width, height, length;
    public Box next;

    Box(double w, double h, double l){
       width=w;
       height=h;
       length=l;
     }
  }

CodePudding user response：

I've modified your code to make it output correct results. Does this solve your problem?

public class Main {
    public static void main(String[] args) {
        Box head;
        try {
            head = LinkedList("ll.txt");
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return;
        }
        
        System.out.println(head);
    }
    // main
    static Box LinkedList(String file) throws FileNotFoundException {
        Scanner scan = new Scanner(new FileReader(file));
        Box head = null;
        Box lastBox = null;
        while (scan.hasNextLine()){
            String line = scan.nextLine();
            String [] arr = line.split(" ");
            Box b = new Box(Double.parseDouble(arr[0]), Double.parseDouble(arr[1]), Double.parseDouble(arr[2]));
            if(lastBox != null) lastBox.next = b;
            if(head == null) head = b;
            lastBox = b;
        }
        return head;
    }
}
//class
class Box{
    private double width, height, length;
    public Box next;

    Box(double w, double h, double l){
        width=w;
        height=h;
        length=l;
    }
}