Calcular a média em Java, salvando o resultado em arquivo TXT

Media.java

import java.io.*;
import java.text.DecimalFormat;

public class Media {

    private static Double n1 = 0.0, n2 = 0.0, n3 = 0.0, n4 = 0.0, media = 0.0;

    public static void main(String[] args) {
        try {
            System.out.println("Informe a nota 1:");
            BufferedReader in1 = new BufferedReader(new InputStreamReader(System.in));
            n1 = Double.parseDouble(in1.readLine());

            System.out.println("Informe a nota 2:");
            BufferedReader in2 = new BufferedReader(new InputStreamReader(System.in));
            n2 = Double.parseDouble(in2.readLine());

            System.out.println("Informe a nota 3:");
            BufferedReader in3 = new BufferedReader(new InputStreamReader(System.in));
            n3 = Double.parseDouble(in3.readLine());

            System.out.println("Informe a nota 4:");
            BufferedReader in4 = new BufferedReader(new InputStreamReader(System.in));
            n4 = Double.parseDouble(in4.readLine());

            media = (n1 + n2 + n3 + n4) / 4;
            DecimalFormat df = new DecimalFormat("#.0");

            System.out.println("A nota 1 informada é: " + n1.toString());
            System.out.println("A nota 2 informada é: " + n2.toString());
            System.out.println("A nota 3 informada é: " + n3.toString());
            System.out.println("A nota 4 informada é: " + n4.toString());
            System.out.println("A média final é: " + df.format(media));

            String filename = "/home/cleberson/www/sandbox/java/learning-java/src/media.txt";
            salva(filename, "A nota 1 informada é: " + n1.toString());
            salva(filename, "A nota 2 informada é: " + n2.toString());
            salva(filename, "A nota 3 informada é: " + n3.toString());
            salva(filename, "A nota 4 informada é: " + n4.toString());
            salva(filename, "A média final é: " + df.format(media));
        } catch (IOException e) {
//            throw new IOException("Problema ao ler o stream de entrada ", e);
        }
    }

    private static void salva(String filename, String linha) {
        try {
            FileWriter file = new FileWriter(filename, true);
            BufferedWriter writer = new BufferedWriter(file);
            writer.write(linha);
            writer.newLine();
            writer.flush();
            writer.close();
        } catch (IOException e) {

        }
    }
}