Problem removing data from an Arraylist

Question

Good afternoon, I am having a certain difficulty in reading and writing the data in an arraylist. The data from my TXT file:

Mark 12345

Rafaela 54321

Kaique 12345

Matheus 54321

Just follow my code:

if( evento.getSource( ) == bENTRAR )
  {
     openFile();
     //Gravando records = new Gravando();
     int i = 0;
     int cont = 0;
     while( i <= grava.getListaMateria().size()-1)
     {
        System.out.println("Login:"+grava.getListaMateria().get(i).getLogin());
        System.out.println("Senha:"+grava.getListaMateria().get(i).getSenha()+"Fezes"+cont);
        if(grava.getListaMateria().get(i).getLogin().equals(l) && grava.getListaMateria().get(i).getSenha().equals(s))
           {
              JOptionPane.showMessageDialog(null,"Login feito com sucesso","Bem vindo",1);
              dispose();
              MenuGUI oples = new MenuGUI();
           }

       i++;
       cont++;
       } 
      JOptionPane.showMessageDialog(null,"Login ou senha incorretos","Desculpe",1);


  }
}

 public void openFile()
 {
  l = tLogin.getText();
  s = Senha.getText();
  try
  {
     input = new Scanner(new File( "login.txt" ));
  } // end try
  catch( FileNotFoundException fileNotFoundException )
  {
     System.err.println( "Error opening file." );
     System.exit( 1 );
  } // end catch


  ArrayList<Gravando> lp = new ArrayList<Gravando>();
  try // read records from file using Scanner object
  {
     while(input.hasNext())
     {
        //Scanner scanner = new Scanner(new File("login.txt"));
        input.useDelimiter(" ");

        grava.setLogin(input.nextLine() /*input.next()*/ ); // read account number
        grava.setSenha(input.nextLine()/*input.next()*/ ); // read first name

        lp.add(grava); 
     } // end try

  }
  catch ( NoSuchElementException elementException )
  {
     System.err.println( "File improperly formed." );
     input.close();
     System.exit( 1 );
  } // end catch
  catch ( IllegalStateException stateException )
  {
     System.err.println( "Error reading from file." );
     System.exit( 1 );
  } // end catch

  grava.setListaMaterias(lp);
  input.close();
 } // end method openFile

The problem is when I perform the commands: System.out.println("Login:"+grava.getListaMateria().get(i).getLogin()); System.out.println("Password:"+grava.getListaMateria(). get(i). getSenha()+"Feces"+cont);

He returns me in my getLogin():Kaique 12345 He returns me in my getSenha(): Matheus 54321

But it was for him returns me in getLogin(): Kaique But it was for it returns me in getSenha(): 12345

I wonder what I’m doing wrong.

   quando tento compilar o metodo que voce me falou da a seguinte mensagem.

    LoginGUI.java:350: error: no suitable method found for add(String[])
        lp.add(linhaArquivo.split(" ")); 
          ^
method Collection.add(String) is not applicable
  (argument mismatch; String[] cannot be converted to String)
method List.add(String) is not applicable
  (argument mismatch; String[] cannot be converted to String)
method AbstractCollection.add(String) is not applicable
  (argument mismatch; String[] cannot be converted to String)
method AbstractList.add(String) is not applicable
  (argument mismatch; String[] cannot be converted to String)
method ArrayList.add(String) is not applicable
  (argument mismatch; String[] cannot be converted to String)

Answer 1

The method nextLine() is returned all line, from your file, at once. I believe that if you use the split() can solve your problem, once this method can split a string, in the patterns you define, and put each part in a String array.

For example:

String linhaArquivo = input.nextLine();
String []valores = new String[2];
valores = linhaArquivo.split(" ");

The code above will cut the String to each blank space, that is, inside the array values, it will be:

valores[0] = "Kaique";
valores[1] = "12345";