Java多客户端游戏服务器

Question

我无法为我制作的游戏制作多客户端服务器。我能够创建一个ServerSocket，建立连接并通过ObjectInputStream和ObjectOutputStream发送数据。我的问题在于涉及多个客户端，据我所知，需要为每个客户端创建一个新线程，但我希望发送和接收的数据被硬编码到客户端类中。我如何允许我的客户发送可变数据？

这是我的客户端类：

 public class Client extends Thread {
private Server server = new Server();
private Socket connection;
private ObjectOutputStream out;
private ObjectInputStream in;

public Client(Socket connection) {
    this.connection = connection;

    this.out = server.objOutStream(this.connection);
    this.in = server.objInStream(this.connection);
}

public void run() {
    while(this.connection.isConnected()) {
        //
        List<String> list = new ArrayList<String>();
        list.add("hello there");
        server.sendData(out, list);
        //
        List<String> recive = new ArrayList<String>();
        recive = server.reveiveData(in);
    }
}

public Socket getConnection() {
    return connection;
 }
}

以下是服务器端：

public ServerSocket createServer(Integer serverPort, Integer serverSize) {
    ServerSocket server = null;
    try {
        server = new ServerSocket(serverPort, serverSize);
        System.out.println("created server");
    } catch (IOException e) {
        e.printStackTrace();
    }
    return server;
}

public Socket makeConnection(ServerSocket server) {
    Socket connection = null;
    try {
        connection = server.accept();
        Client client = new Client(connection);
        client.start();
        System.out.println("connection made with " + connection.getInetAddress().getHostAddress());
    } catch (IOException e) {
        e.printStackTrace();
    }
    return connection;
}

public ObjectInputStream objInStream(Socket connection) {
    ObjectInputStream in = null;
    try {
        in = new ObjectInputStream(connection.getInputStream());
    } catch (IOException e) {
        e.printStackTrace();
    }
    return in;
}

public ObjectOutputStream objOutStream(Socket connection) {
    ObjectOutputStream out = null;
    try {
        out = new ObjectOutputStream(connection.getOutputStream());
    } catch (IOException e) {
        e.printStackTrace();
    }
    return out;
}

public void sendData(ObjectOutputStream out, List<String> list) {
    try {
        out.writeObject(list);
        out.flush();
        System.out.println("sending " + list);
    } catch (IOException e) {
        e.printStackTrace();
    }
}

public List<String> reveiveData(ObjectInputStream in) {
    List<String> list = null;
    try {
        list = (List<String>) in.readObject();
    } catch (IOException | ClassNotFoundException e) {
        e.printStackTrace();
    }
    return list;
}

public Socket joinServer(String serverIP, Integer serverPort) {
    Socket connection = null;
    try {
        connection = new Socket(InetAddress.getByName(serverIP), serverPort); System.out.println("joined");
    } catch (IOException e) {
        e.printStackTrace();
    }
    return connection;
}

public void stop(Socket connection) {
    System.out.println("closing");
    try {
        if(connection.isInputShutdown() == false) {
            connection.getInputStream().close();
        }
        if(connection.isOutputShutdown() == false) {
            connection.getOutputStream().close();
        }
        if(connection.isConnected() == true) {
            connection.close();
        }
        System.exit(0);
    } catch (IOException e) {
        e.printStackTrace();
    }
}

在我的mian课程中我运行：

        try {
        if(connection == null) {
            connection = server.makeConnection(serverSocket);
            in = server.objInStream(connection);
            out = server.objOutStream(connection);
        }else {
            //readlist
            List<String> readList = (List<String>) in.readObject();
            System.out.println("reciving: " + readList);

            //writelist
            List<String> writeList = new ArrayList<String>();
            writeList.add("hi");
            out.writeObject(writeList);
            System.out.println("sending: " + writeList);
        }
    }catch(IOException | ClassNotFoundException e) {
        e.printStackTrace();
    }