Question

我正在开展一个项目来实施游戏＆＃34; Monopoly＆＃34;在Java中。我目前在客户端代码上设置了一个GUI，将文本输入到聊天框（或发送命令）到服务器。

我的Controller.java类是启动GUI的代码。当用户输入游戏服务器的IP和端口并命中提交时，侦听该Socket的服务器然后实例化Controller.java内部类ClientServiceThread的线程。这个类应该在GUI之间发送消息 - 客户端 - 服务器。

我的问题是在外部类（Controller.java）中我有一个名为＆＃34; messageText＆＃34;的实例变量。稍后当用户向Chatbox输入消息时，我将该文本分配给＆＃34; messageText＆＃34;变量。但是，当我尝试在ClientServiceThread中获取该变量时，它始终为null。我相信这是因为服务器同时创建了一个新客户端和一个新控制器，这意味着我试图获得的变量实际上没有被修改过。

服务器代码段

public void run() {

    try {
        myServerSocket = new ServerSocket(8888);
    } catch(IOException ioe) {
        System.out.println("Could not create server socket on port 8888. Quitting.");
        System.exit(-1);
    }

    System.out.println("Server successfully started");

    while(ServerOn) {
        try {
            Socket clientSocket = myServerSocket.accept();
            Controller.ClientServiceThread cliThread = new Controller().new ClientServiceThread(clientSocket, clientidnum);
            cliThread.start();

            //adds clients to array in order they join
            connectedClients[clientidnum] = cliThread;

            //increments connected ID client var
            clientidnum++;
        } catch(IOException ioe) {
            System.out.println("Exception found on accept. Ignoring. Stack Trace :");
            ioe.printStackTrace();
        }
    }

Controller.java代码段

public class Controller extends Application implements Initializable  {

    Socket myClientSocket;
    boolean m_bRunThread = true;
    String hostname;
    int hostportnumber;
    private ObservableList<String> chatMessages = FXCollections.observableArrayList();
    String messageText = "";

    private void handleChatAction(ActionEvent event) throws IOException {
        if (event.getSource() == sendchatButton){
            String chat = chatInput.getText();
            if(chat != null && !chat.trim().isEmpty()) {
                chatMessages.add(chat);
                messageText = chat;
                chatmessagesList.setItems(chatMessages);
                chatmessagesList.scrollTo(chatMessages.size());
            }
            chatInput.clear();
        }
}

内部类ClientServiceThread代码段

class ClientServiceThread extends Thread {
    Socket myClientSocket;
    boolean m_bRunThread = true;
    String hostname;
    int hostportnumber;
    int id;

    public ClientServiceThread() {
        super();
    }

    ClientServiceThread(Socket s, int clientid) {
        myClientSocket = s;
        id = clientid;
    }

    public String getTextField(){
        if(Controller.this.messageText != "") {
            return Controller.this.messageText;
        }
        else {
            return "";
        }
    }

    public void run() {

        BufferedReader in = null;
        PrintWriter out = null;
        System.out.println("Accepted Client Address - " + myClientSocket.getInetAddress().getHostName());

        try {
            in = new BufferedReader(new InputStreamReader(myClientSocket.getInputStream()));
            out = new PrintWriter(new OutputStreamWriter(myClientSocket.getOutputStream()));

            while(m_bRunThread) {
                String clientCommand = getTextField();
                System.out.println("Client Says :" + clientCommand);

我为巨大的代码墙道歉。我已经删除了数百行代码，以减少筛选所需的数量。这个错误确实阻碍了我，除非客户端可以与服务器通信，否则我无法开发实际的游戏。

如果您希望查看完整的代码文件，可以使用以下链接。谢谢！

https://gist.github.com/anonymous/0961189791b8127598b3b3d7ca527987

在Inner Class可以使用它之前，外部类中的实例变量String被设置为null

0 个答案: