I want to alphabetize my “user table” (.txt) using java

there is my code

public void Ordena(File fichero) throws FileNotFoundException, IOException{

    String cadena2;
    BufferedWriter in = null;
    String ruta2 = "C:\Users\estae\Desktop\clase\BaseDatos2.txt";
    File ficheroSalida = new File(ruta2);

    FileReader fread = new FileReader(fichero);
    BufferedReader baca = new BufferedReader(fread);
    while((cadena2 = baca.readLine())!=null) {

        String linUsu [] = cadena2.split ("/n");


        for(String linea : linUsu){

I want to sort the contents of the file “fichero” alphabetically and i did what u see up, the problem is the program take the text but didn’t organice it (each lane in the txt is type: Name;Surname;date;Sex), when i print “linea” i see everything the same as before.
Some idea about it?