public class CipherConnection {

private String password = "abcdef0123456789";
private Key key;
private Cipher c;
private OutputStream os;
private InputStream is;
private Socket s;

public CipherConnection(Socket s) {
    try {
        this.s = s;
        os = s.getOutputStream();
        is = s.getInputStream();
        key = new SecretKeySpec(password.getBytes(), "AES");

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


void send(byte[] b) {
    try {
        c = Cipher.getInstance("AES");
        c.init(Cipher.ENCRYPT_MODE, key);
        CipherOutputStream cos = new CipherOutputStream(os, c);
        cos.write(b);
    } catch(Exception e) {
        e.printStackTrace();
    }
}

void send(byte b) {
    byte[] bb = new byte[1];
    bb[0] = b;
    send(bb);
}

byte[] receive() {
    try {
        int b;
        Vector v = new Vector();
        c = Cipher.getInstance("AES");
        c.init(Cipher.DECRYPT_MODE, key);
        CipherInputStream cis = new CipherInputStream(is, c);
        b = cis.read();
        while ( b != -1) {
            v.add(b);
            b = cis.read();
        }

        return toByteArray(v);
    } catch(Exception e) {
        e.printStackTrace();
        return null;
    }
}

byte[] toByteArray(Vector v) {
    byte[] b = new byte[v.size()];
    int i = 0;
    while (!v.isEmpty()) {
        b[i] = (byte)v.remove(i);
        i++;
    }
    return null;
}

void close() {
    try {
        os.close();
        is.close();
    } catch (Exception e) {
        e.printStackTrace();
    }

}

boolean isClosed() {
    return s.isClosed();
}

public class TestServer {

static CipherConnection co;
public static void main(String[] args) {
    try {

        byte[] b;
        Socket s = new ServerSocket(3242).accept();
        co = new CipherConnection(s);
        b = co.receive();
        System.out.println(new String(b));
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public class TestClient {

static CipherConnection ci;
/**
 * @param args the command line arguments
 */
public static void main(String[] args) {
    try {
        Socket s = new Socket("127.0.0.1", 3242);

        byte[] b;
        b = "Hello".getBytes();
        ci = new CipherConnection(s);
        ci.send(b);
    } catch (Exception e) {
        e.printStackTrace();
    }

}