How to change the character encoding so that my FileWriter writes in ISO_8859-1 format?

I have the following program that reads a text file, changes the format of a specified date (Issue Date) and then writes everything back to a different file with the correct date format.

The issue is that when it rewrites the file it does it in UTF-8 and I need it to rewrite it in ISO_8859-1

How can I do this ?

public class DateFormater {

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

        if(args.length == 0){
            System.out.println("Faltan argumentos");
            return;
        }

        try {
            System.out.println("Leyendo Archivos de Configuración ... ");
            Configuration conf = new Configuration("../resources/Configuracion.json");

            final String origin = (String) conf.getJson().get("origen") +args[0];
            final String destiny = (String) conf.getJson().get("destino")+args[1];
            FileInputStream fstream = new FileInputStream(origin);
            FileWriter writer = new FileWriter(destiny);
            BufferedReader br = new BufferedReader(new InputStreamReader(fstream));
            String strLine;

            while ((strLine = br.readLine()) != null)   {
                if(strLine.contains("Fecha de Emision: ")){
                    String date = strLine.substring(83,93);
                    SimpleDateFormat format = new SimpleDateFormat("MM/dd/YYYY");
                    String dateString = format.format(new Date(date));
                    String newDate = strLine.replace(date, dateString);
                    writer.write(newDate+"\n");
                }
                else{
                    writer.write(strLine+"\n");
                }
            }
            br.close();
            writer.close();
            System.out.println("El programa ha finalizado con exito");
            System.out.println("El nuevo archivo ha sido generado en " + destiny);
        } catch (FileNotFoundException ex) {
            Logger.getLogger(DateFormater.class.getName()).log(Level.SEVERE, null, ex);
        } catch (ParseException ex) {
            Logger.getLogger(DateFormater.class.getName()).log(Level.SEVERE, null, ex);
        }
    }   
}