Java Text Streams

Your code was very good, just missing small details. I turned here and adapted.

First problem: The file path must be complete. I put the file in c: \ and the filename passed "C:\alunos.txt" (notice that there are two slashes to escape the other and java does not think I want to escape the letter 'a' from students) and stopped giving exception saying which could not find the file.

Second problem: I did not understand why it called super in the second constructor instead of doing the first one. super is used to call methods of a parent class, as its class does not extend any other, I did not understand super (). So I changed the super () to:

    this.nome = nome;
    this.notaGA = Float.parseFloat(notaGA);
    this.notaGB = Float.parseFloat(notaGB);   

Third problem: I found it interesting that you used String.format but you ate some s where it should be %s . Fixed:

Matricula: %s\nNome: %s\nNota GA: %s\nNota GB:%s\r\n

At the suggestion of IDE I changed the iteration of the array to a foreach:

     for (Aluno a1 : a)
     {
         System.out.println(a1);
     }

Here are the modified files working:

Student.java

public class Aluno 
{
    protected String matricula;
    protected String nome;
    protected Float notaGA;
    protected Float notaGB;


    public Aluno(String matricula, String nome, Float notaGA, Float notaGB) 
    {

        this.matricula = matricula;
        this.nome = nome;
        this.notaGA = notaGA;
        this.notaGB = notaGB;
    }


    public Aluno(String nome, String notaGA, String notaGB) 
    {
        //super(); // ?

        this.nome = nome;
        this.notaGA = Float.parseFloat(notaGA);
        this.notaGB = Float.parseFloat(notaGB);   
    }


    public String getMatricula() 
    {
        return matricula;
    }

    public void setMatricula(String matricula) 
    {
        this.matricula = matricula;
    }

    public String getNome() 
    {
        return nome;
    }

    public void setNome(String nome) 
    {
        this.nome = nome;
    }

    public Float getNotaGA() 
    {
        return notaGA;
    }

    public void setNotaGA(Float notaGA) 
    {
        this.notaGA = notaGA;
    }

    public Float getNotaGB() 
    {
        return notaGB;
    }

    public void setNotaGB(Float notaGB) 
    {
        this.notaGB = notaGB;
    }

    public String toString()
    {
        return String.format("Matricula: %s\nNome: %s\nNota GA: %s\nNota GB:%s\r\n", 
                getMatricula(),
                getNome(),
                getNotaGA(),
                getNotaGB());
    }

}

UploadAlumni.java

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;


public class CarregaAlunos
{
    protected static Aluno constroiAluno(String linha)
    {
        String atributos[] = linha.split(",");
        Aluno a = new Aluno(atributos[0], atributos[1], atributos[2]);
        return a;
    }

    public static Aluno[] carregaArquivo(String arquivo) throws IOException
    {
        Aluno alunos[]      = new Aluno[5];
        FileReader fr       = new FileReader(arquivo);
        BufferedReader br   = new BufferedReader(fr);
        String linha;

        int cont = 0;
        while ((linha = br.readLine()) != null)
        {
            Aluno a = constroiAluno(linha);
            alunos[cont] = a;
            cont++;
        }


        br.close();
        return alunos;

 }

    public static void main(String[] args) 
    {
        try
        {
            Aluno a[] = carregaArquivo("C:\alunos.txt");

            for (Aluno a1 : a)
            {
                System.out.println(a1);
            }

        }
        catch(IOException e)
        {
            e.printStackTrace();
        }

    }

}

Any questions please ask in the comments. If that answer has helped you, give it a moral by marking it as an accepted response and by clicking on the little box above to give me reputation points.