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I'm trying to simply encrypt some text, save it in a text file, and load/decrypt it.

Using the tutorials on the Java website, I've been using the code:

public class MainClass {
  public static void main(String args[]) throws Exception {
    KeyGenerator kg = KeyGenerator.getInstance("DES");
    kg.init(new SecureRandom());
    SecretKey key = kg.generateKey();
    SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
    Class spec = Class.forName("javax.crypto.spec.DESKeySpec");
    DESKeySpec ks = (DESKeySpec) skf.getKeySpec(key, spec);
    ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("keyfile"));
    oos.writeObject(ks.getKey());

    Cipher c = Cipher.getInstance("DES/CFB8/NoPadding");
    c.init(Cipher.ENCRYPT_MODE, key);
    CipherOutputStream cos = new CipherOutputStream(new FileOutputStream("ciphertext"), c);
    PrintWriter pw = new PrintWriter(new OutputStreamWriter(cos));
    pw.println("Stand and unfold yourself");
    pw.close();
    oos.writeObject(c.getIV());
    oos.close();
  }
}

To save the encrypted text file.

And I've been using the code:

public class MainClass {
  public static void main(String args[]) throws Exception {
    ObjectInputStream ois = new ObjectInputStream(new FileInputStream("keyfile"));
    DESKeySpec ks = new DESKeySpec((byte[]) ois.readObject());
    SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
    SecretKey key = skf.generateSecret(ks);

    Cipher c = Cipher.getInstance("DES/CFB8/NoPadding");
    c.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec((byte[]) ois.readObject()));
    CipherInputStream cis = new CipherInputStream(new FileInputStream("ciphertext"), c);
    BufferedReader br = new BufferedReader(new InputStreamReader(cis));
    System.out.println(br.readLine());
  }
}

to load and decrypt the text file. This gives the output:

Stand and unfold yourself!

I then changed the first function so that it re-uses the same SecretKey rather than generating a new one.

   ObjectInputStream ois = new ObjectInputStream(new FileInputStream("keyfile"));
    DESKeySpec ks = new DESKeySpec((byte[]) ois.readObject());
    SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
    SecretKey key = skf.generateSecret(ks);

    Cipher c = Cipher.getInstance("DES/CFB8/NoPadding");
    c.init(Cipher.ENCRYPT_MODE, key);
    CipherOutputStream cos = new CipherOutputStream(new FileOutputStream("ciphertext"), c);
    PrintWriter pw = new PrintWriter(new OutputStreamWriter(cos));
    pw.println("Stand and unfold yourself");
    pw.close();

However, when I run the program - the output is scrambled! Instead of the above output, I get the following

F{�&;�d unfold yourself
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