Android - How to decrypt an XML file?

Question

I am trying to to download and decrypt an encrypted XML file.

I have implemented the download part and have tested with an unencrypted file and it works fine.

However I now need to be able to download an XML file that has been encrypted using AES and the key "XXXX"

So I am only concerned with decryption as the encryption on the XML file is already done.

Here is my code so far:

---

public NodeList getRoutingDoc(){
        URL url;
        NodeList nl = null;

        try{
            String xmlFeed = context.getString(R.string.xml_feed) + IMEI + ".xml";
            try {
                url = new URL(xmlFeed);
                URLConnection urlConnection;
                urlConnection = url.openConnection();    
                HttpURLConnection httpConnection = (HttpURLConnection) urlConnection;    
                int responseCode = httpConnection.getResponseCode();

                if(responseCode == HttpURLConnection.HTTP_OK){
                    String bytes = toHex("XXXX");
                    Key skeySpec = new SecretKeySpec(toByte(bytes), "AES");

                    InputStream in = httpConnection.getInputStream();
                    System.out.println(toByte(bytes));
                    Cipher c = Cipher.getInstance("AES/CFB8/NoPadding");
                    c.init(Cipher.DECRYPT_MODE, skeySpec, new IvParameterSpec(toByte(bytes)));
                    CipherInputStream cis = new CipherInputStream(in, c);
                    cis.read(new byte[16]);
                    BufferedReader br = new BufferedReader(new InputStreamReader(cis));
                    System.out.println("Got message");
                    System.out.println(br.readLine());

                    DocumentBuilderFactory dbf;
                    dbf = DocumentBuilderFactory.newInstance();
                    DocumentBuilder db = dbf.newDocumentBuilder();

                    Document dom = db.parse(in);
                    //cis.close();
                    Element docEle = dom.getDocumentElement();

                    nl = docEle.getElementsByTagName(TAG_CHAR);

                    }        
            }
            catch (MalformedURLException e) {

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

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

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

                e.printStackTrace();
            } catch (InvalidKeyException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (InvalidAlgorithmParameterException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (NoSuchAlgorithmException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (NoSuchPaddingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            }
            finally{

            }
        return nl;
    }

---

At the minute I am trying to decrypt the whole file using CipherInputStream is this the correct approach?

My code above gives me the following exception:

WARN/System.err(5274): java.io.IOException: last block incomplete in decryption

Is this a setup error or what might be causing this error?

Are there any tutorials on how to decrypt an XML file in Android/Java?

Am I going in the right direction as to how to decrypt the file or is my code completely wrong?

EDIT:

I have updated my code to the latest version I have.

I am now using the CipherInputStream properly I think and getting the file in but the System.out.println gives me the following output:

INFO/System.out(7880): �=k�KV�a��_|F��(# -�Ñ��u���n�|��~����9�<í�|T��sUWÇ�9�qeo�M%�t�V�V�3Q"�    T�Yq?��E����H%fo���M�un��-���È������<d��{���{�!�[&��%��M�.�jq+��,�b����� ��~����)��*ܨ)��>��i���b�_"��F)�`"�

So it looks as if its no decrypting it at all or not decrypting it properly??

Can anyone see what I am doing wrong?

Another update:

I have changed the code to test encryption first and then decryption so the code is now as follows:

Cipher c = Cipher.getInstance("AES/CFB8/NoPadding");

ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(keyFile));
oos.writeObject(skeySpec);

c.init(Cipher.ENCRYPT_MODE, skeySpec);
CipherOutputStream cos = new CipherOutputStream(new FileOutputStream(testFile), c);
PrintWriter pw = new PrintWriter(new OutputStreamWriter(cos));
pw.println("Stand and unfold yourself");
pw.close();
oos.writeObject(c.getIV());
oos.close(); 

c.init(Cipher.DECRYPT_MODE, skeySpec, new IvParameterSpec(toByte(bytes)));
CipherInputStream cis = new CipherInputStream(new FileInputStream(testFile), c);
Log.d("XXXX", br.readLine());

This log now prints out the following:

DEBUG/(13642): �l�Ť���Õ*(��� yourself

So it looks like its decoding the last part of it but not the rest?

Any ideas?