JavaFX和网络

抱歉,如果这样的事情已经被问到,我什么都没找到,但我不确定是什么问题,所以我真的不知道该找什么.

服务器：

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Date;

import javafx.scene.Scene;
import javafx.scene.control.TextArea;
import javafx.stage.Stage;

public class ChatServer extends Stage {
    TextArea informationArea = new TextArea();
    String message = null;

    public ChatServer() {
        informationArea.setEditable(false);
        setTitle("Chat Server");
        setScene(new Scene(informationArea,500,300));
        show();

        try {
            ServerSocket serverSocket = new ServerSocket(8000);
            informationArea.appendText("Server started at " + new Date() + 'n');

            int clientNumber = 1;

            while(true) {
                Socket socket = serverSocket.accept();
                InetAddress inetAddress = socket.getInetAddress();

                informationArea.appendText(
                    "Client: " + clientNumber++
                    + "nthost name: " + inetAddress.getHostName()
                    + "ntIP address " + inetAddress.getHostAddress() + "nn"
                );

                ClientHandler task = new ClientHandler(socket);
                new Thread(task).start();
            }
        } catch(IOException ex) {
            System.err.println(ex);
        }
    }

    class ClientHandler implements Runnable {
        private Socket socket;

        ClientHandler(Socket socket) {
            this.socket = socket;
        }

        @Override
        public void run() {
            try {
                DataInputStream inputFromClient = new DataInputStream(socket.getInputStream());
                DataOutputStream outputToClient = new DataOutputStream(socket.getOutputStream());

                while (true) {
                    if (message != null) {
                        outputToClient.writeUTF(message);
                    }
                    message = inputFromClient.readUTF();
                }
            } catch(IOException e) {
                System.err.println(e);
            }
        }
    }
}

运行它的类：

import javafx.application.Application;
import javafx.stage.Stage;

public class RunChatServer extends Application {
    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage stage) {
        stage = new ChatServer();
    }
}

我很欣赏输入错误的原因,为什么,实现这个目标的正确方法,以及任何风格的建议,因为这是我的第一次尝试,而我不知道实现这一目标的传统方法.

更新：
我想也许它与阻止UI线程有关,我添加了导入javafx.concurrent.Task并重构了我的ClientHandler类,如下所示：

class ClientHandler extends Task {
        private Socket socket;

        ClientHandler(Socket socket) {
            this.socket = socket;
        }

        @Override
        public Void call() {
            try {
                DataInputStream inputFromClient = new DataInputStream(socket.getInputStream());
                DataOutputStream outputToClient = new DataOutputStream(socket.getOutputStream());

                while (true) {
                    if (message != null) {
                        outputToClient.writeUTF(message);
                        outputToClient.flush();
                    }
                    message = inputFromClient.readUTF();
                }
            } catch(IOException e) {
                System.err.println(e);
            }
            return null;
        }
    }

但这没有解决任何问题……