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Thread: How can I read a file and store it's objects into my custom linked list?

  1. #1
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    Default How can I read a file and store it's objects into my custom linked list?

    Basically, I am not using any of the Java API classes such as ArrayLists or LinkedLists, as I have created my own custom linked list class which in this case is named FoodList. I am trying to figure out a way to read each line from a file where each line is an object, and store it in FoodList.

    I've looked at many examples of reading files online, but none of them were for a custom linked list.

    HTML Code:
    package lab9;
    
    import java.io.File;
    import java.io.FileNotFoundException;
    import java.util.*;
    
    public class Console {
    	
        FoodList x = new FoodList();
    	
    	public Console(){
    		this.x = new FoodList();
    	}
    	
    	public void Display() {
    		
    		System.out.println("============================================================================");
    		System.out.println("Name                Food Group          Calories            Daily percentage   ");
    		System.out.println("============================================================================");
    		
            File f = new File("food.txt");
            
            try {
            	Scanner scan = new Scanner(f);  //What I tried to do to read in objects from file
            	
                while(scan.hasNextLine()){
                    String line = scan.nextLine();
                    String[] details = new String[4];
                    details = line.split(" ");
                    String name = details[0];
                    String group = details[1];
                    int calories = Integer.parseInt(details[2]);
                    double percentage = Double.parseDouble(details[3]);
                    x.add(new Food(name, group, calories, percentage));
                }
                
                System.out.println(x);
    
            } catch (FileNotFoundException e) {
                e.printStackTrace();
                System.out.println("Not working");
            }
        }
    	
    }

  2. #2
    Super Moderator Norm's Avatar
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    Default Re: How can I read a file and store it's objects into my custom linked list?

    What happens when you compile and execute your program?
    Can you copy the output and post it there so we can see what it is doing?
    What is wrong with what the program is doing?
    What do you want it to do differently?

    Note: x is a poor name for a variable that references a list and f for a file.
    If you don't understand my answer, don't ignore it, ask a question.

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