java.net.SocketException: connection reset on reading bytes

i am trying to create a little server in java using sockets. The sockets are connected but when i send data from my client to my server it gives an exception.

stacktrace (UPDATED):

    IOException on socket listen: java.net.SocketException: Connection reset
    java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(Unknown Source)
    at java.io.ObjectInputStream$PeekInputStream.read(Unknown Source)
    at java.io.ObjectInputStream$PeekInputStream.readFully(Unknown Source)
    at java.io.ObjectInputStream$BlockDataInputStream.readShort(Unknown Source)
    at java.io.ObjectInputStream.readStreamHeader(Unknown Source)
    at java.io.ObjectInputStream.<init>(Unknown Source)
    at org.codox.game.network.NetworkController$doComms.run(NetworkController.java:81)
    at java.lang.Thread.run(Unknown Source)

if you need more information tell me

any suggestions are welcome

thx

-- EDITED --

full server code:

class doComms implements Runnable
{
    private Socket server;
    PackageHandler packageHandler;
    doComms(Socket server)
    {
        this.server = server;
        packageHandler = new PackageHandler();
    }

    public void run()
    {

        try
        {
            ObjectInputStream ois = new ObjectInputStream(server.getInputStream());     
            ClientPackage clientPack = (ClientPackage) ois.readObject();

            RespondPackage rp = packageHandler.handlePackage(clientPack);

            ObjectOutputStream ous = new ObjectOutputStream(server.getOutputStream());

            ous.writeObject(rp);
            ous.flush();

            server.close();
            System.out.println("Connection was finished and closed.");

        } catch (ClassNotFoundException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException ioe)
        {
            System.out.println("IOException on socket listen: " + ioe);
            ioe.printStackTrace();
        }
    }
}

full client code:

SocketHints hints = new SocketHints();
        hints.keepAlive = true;
        hints.connectTimeout = 2000;

        Socket socket;
        try
        {
            socket = Gdx.net.newClientSocket(Protocol.TCP, "127.0.0.1", 12346, hints);

            ClientPackage client = new ClientPackage();
            client.setRequestType(RequestType.ping);

            ObjectOutputStream ous = new ObjectOutputStream(socket.getOutputStream());

            ous.writeObject(client);
            ous.flush();

            ObjectInputStream ois = new ObjectInputStream(socket.getInputStream());

            RespondPackage response = (RespondPackage) ois.readObject();
            System.out.println("Respone type = " + response.getRequestType());

        } catch (UnknownHostException e1)
        {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        } catch (IOException e1)
        {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        } catch (Exception e)
        {

        }