How to read the .csv file and write it in a list?

In this part:

listaAtletas.add(new Account(accountHolder, accountNumber, accountBalance));

  

You seem to add a Account and not a Atleta .

I think that there is a good part of the error. Other than that, I did not understand how you are creating a new athlete , and adding in the list (is missing code?)

Anyway, I've changed your code (quite, sorry!) for testing, and I believe you can use this code to fix yours:

import java.util.*;
import java.io.*;

public class MaratonaAdmin {

    static List<Atleta> listaAtletas;

    public static void main(String[] args) throws FileNotFoundException {

        listaAtletas = new ArrayList<>();
        lerOsAtletas();

        System.out.println("Tamanho da lista " + listaAtletas.size());

        for (Atleta atl : listaAtletas) {
            System.out.println("Atleta no.: " + atl.numero);
            System.out.println("Nome: " + atl.nome);
            System.out.println("Grupo: " + atl.idadeGrupo);
            System.out.println("Tempo: " + atl.tempo);
            System.out.println("#######");
        }
    }

    public static void lerOsAtletas() throws FileNotFoundException {

        FileReader arq = new FileReader("C://Users//danie//Documents//test.csv");

        Scanner bufferedScanner = new Scanner(new BufferedReader(arq));
        try {
            while (bufferedScanner.hasNextLine()) {
                String linhaCurrente = bufferedScanner.nextLine();
                Scanner linhaScanner = new Scanner(linhaCurrente);
                linhaScanner.useDelimiter(",");
                listaAtletas.add(new Atleta(linhaScanner.next(),
                  linhaScanner.next(), linhaScanner.next()));
                linhaScanner.close();
            }
        } catch (Exception anException) {
            System.out.println("Erro: " + anException);
        } finally {
            try {
                bufferedScanner.close();
            } catch (Exception anException) {
                System.out.println("Error: " + anException);
            }
        }
    }
}

  

I had to change the class Atleta also (for reason explained above):

public class Atleta {
    private static int proximoNumero = 1;   
    public int numero;
    public String nome;
    public String idadeGrupo;
    public String tempo;

    public Atleta(String nome, String idadeGrupo, String tempo) {
        this.nome = nome;
        this.idadeGrupo = idadeGrupo;
        this.tempo = tempo;
        this.numero = Atleta.proximoNumero;
        Atleta.proximoNumero++;
    }
}

In addition, your int tempo; should not work, because the program reads String of .csv , does not it? The conversion will have to be made at another time (I did not include the conversion to simplify the code).

  

.csv used for testing:

stackoverflow,junior,2:02:57
Torre Eiffel,senior,3:14:41
Empire State,media,4:21:18

  

Result:

Tamanho da lista 3
Atleta no.: 1
Nome: stackoverflow
Grupo: junior
Tempo: 2:02:57
#######
Atleta no.: 2
Nome: Torre Eiffel
Grupo: senior
Tempo: 3:14:41
#######
Atleta no.: 3
Nome: Empire State
Grupo: media
Tempo: 4:21:18
#######

Your version did not work but it helped me find the error I had in the code. Thanks for the help and here is the complete code.

import java.util.*;
import java.io.*;

/**
 * Class MaratonaAdmin - administra a maratona
 */
public class MaratonaAdmin
{

   //private Atleta osAtletas;
   static List<Atleta> listaAtletas;

   /**
    * Constructor para os objectos da class MaratonaAdmin
    */
   public MaratonaAdmin() throws FileNotFoundException
   {
      listaAtletas = new ArrayList<>();
      lerOsAtletas(); 
      for (Atleta atl : listaAtletas) {
          System.out.println("Atleta no.: " + atl.numero);
          System.out.println("Nome: " + atl.nome);
          System.out.println("Grupo: " + atl.idadeGrupo);
          System.out.println("Tempo: " + atl.tempo);
          System.out.println("#######");
        }

   }

   /**
    * Metodo que lê de arquive .CSV
    * Não tem argumento
    * Não retorna valores
    */
   public static void lerOsAtletas() throws FileNotFoundException
   {
        Scanner bufferedScanner = new Scanner(new BufferedReader(new FileReader("C://Users//danie//Documents//test.csv")));
        try {
            while (bufferedScanner.hasNextLine()) {
                String linhaCurrente = bufferedScanner.nextLine();
                Scanner linhaScanner = new Scanner(linhaCurrente);
                linhaScanner.useDelimiter(",");
                listaAtletas.add(new Atleta(linhaScanner.next(),
                  linhaScanner.next(), linhaScanner.next()));
                linhaScanner.close();
            }
        } catch (Exception anException) {
            System.out.println("Erro: " + anException);
        } finally {
            try {
                bufferedScanner.close();
            } catch (Exception anException) {
                System.out.println("Error: " + anException);
            }
        }
   }
}