public byte[] format(AuthorizedKeys keys) 
{
        throw new java.lang.UnsupportedOperationException(
            "SSHTools authorized keys format requries seperate key files!");
}

 public byte[] format(AuthorizedKeys keys,
    AuthorizedKeysFileSaver saver) throws IOException, InvalidSshKeyException 
{
        Authorization authorization = new Authorization();
        SshPublicKeyFile pubfile;
        SECSHPublicKeyFormat secsh = new SECSHPublicKeyFormat();
        Map.Entry entry;
        for (Iterator it = keys.getAuthorizedKeys().entrySet().iterator();
                (it != null) && it.hasNext();) {
            entry = (Map.Entry) it.next();
            // Write out the public key file
            String username = (String) entry.getValue();
            String filename = username + ".pub";
            secsh.setComment(username);
            pubfile = SshPublicKeyFile.create((SshPublicKey) entry.getKey(),
                    secsh);
            saver.saveFile(filename, pubfile.toString().getBytes("US-ASCII"));
            // Write out the key entry
            authorization.addKey(filename);
        }
        return authorization.toString().getBytes("US-ASCII");
}

 public boolean requiresKeyFiles() 
{
        return true;
}

 public AuthorizedKeys unformat(byte[] formatted) 
{
        throw new java.lang.UnsupportedOperationException(
            "SSHTools authorized keys format requries seperate key files!");
}

 public AuthorizedKeys unformat(byte[] formatted,
    AuthorizedKeysFileLoader loader) throws IOException, InvalidSshKeyException 
{
        try {
            AuthorizedKeys keys = new AuthorizedKeys();
            Authorization authorization = new Authorization(new ByteArrayInputStream(
                        formatted));
            List keyfiles = authorization.getAuthorizedKeys();
            Iterator it = keyfiles.iterator();
            String filename;
            SshPublicKeyFile pubfile;
            String username;
            while (it.hasNext()) {
                filename = (String) it.next();
                pubfile = SshPublicKeyFile.parse(loader.loadFile(filename));
                username = filename.substring(0, filename.length() - 4);
                keys.addKey(username, pubfile.toPublicKey());
            }
            return keys;
        } catch (ParserConfigurationException ex) {
            throw new IOException("Failed to read authorization file: " +
                ex.getMessage());
        } catch (SAXException ex) {
            throw new IOException("Failed to read authorization file: " +
                ex.getMessage());
        }
}