verifying a signature

[nisaa15]

HI,

I wanted to know how could I retrieve a sealed object from a signed object and then verify it?

Heres my attempt:

if(!sending){//if we are receiving (being the server)

        ServerSocket server = new ServerSocket(port);  
        Socket s = server.accept(); 
        ObjectInputStream oin = new OnbjectInputStream(s.getInputStream());
        ObjectOutputStream oout = new ObjectOutputStream(s.getOutputStream());

        System.out.println("Please enter a passphrase:");
        //asks user to enter their passphrase
        System.out.println("Type your message: ");
        //server retrieves the clients message
        InputStreamReader message = new InputStreamReader(System.in);
        BufferedReader console = new BufferedReader(message);

        String message = null;
        try { 
        secretMessage = console.readLine(); 
        } 
        catch (IOException e) { message = "<" + e + ">";}


        //gets the object from the sender
        oin.readObject(signedobject);

        SealedObject so = signedobject.getObject();  
        //retrieves the Sealed object   

        Public key = getKey(user);
        Signature sig = Signature.getInstance("DSA");
        sig.init(key);
        sig.update();


        //decrypting the object
        SealedObject so = (SealedObject) oin.readObject();
        Cipher cipher = Cipher.getInstance(algorithm);

        if(sig.verify(key)){
        verifies = true;
        System.out.println("The signature has successfully verified");
        System.out(secretMessage);

        cipher.init(Cipher.DECRYPT_MODE, key);
        SecretObject secretObject = (SecretObject) so.getObject(cipher);
        //retrieves the original object with the necryption removed.    
        }
        else{
        System.out.println("The signature has failed to verify, please recheck your passphrase");

please let me know if you spot any other errors
cheers.