问 java.net.SocketException:主机中的软件中止了已建立的连接。

EN

我试图使用Java套接字制作一个简单的聊天应用程序，下面是服务器的代码：

    public ServerSocket ss;
    public ArrayList<Client> Clients = new ArrayList<Client>();
    String Alphabets = "AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz0123456789";
    public Server() throws IOException 
        ss = new ServerSocket(1111);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setLayout(null);
        this.setResizable(false);
        this.setSize(400,150);
        this.getContentPane().setBackground(Color.BLACK);
        this.setTitle("Server");
        JLabel label = new JLabel("Server Running");
        label.setForeground(Color.WHITE);
        label.setBounds(15,25,350,60);
        label.setFont(new Font(Font.SANS_SERIF,Font.PLAIN,50));
        this.add(label);
        this.setVisible(true);
        while(true) 
            Socket socket = ss.accept();
            DataOutputStream dout = new DataOutputStream(socket.getOutputStream());
            String id = getId();
            dout.writeUTF(id);
            Client c = new Client(socket,id);
            dout.close();
            dout.flush();
    String getId() 
        Random rand = new Random();
        String id = ""; 
        for(int i = 0;i < 6;i++) 
            char i3 = Alphabets.charAt(rand.nextInt(0,Alphabets.length()));
            id += i3;       
        return id;
    }

一切正常，当客户端连接时，他获得一个id并被添加到 Clients --这里是客户机连接的代码：

    public String Connect() throws UnknownHostException, IOException 
        mySocket = new Socket("localhost",1111);
        DataInputStream din = new DataInputStream(mySocket.getInputStream());
        String id = din.readUTF();
        return id;