java套接字线程正在工作，但没有消息

大家好，我正在尝试创建一个小型的客户机-服务器或服务器-客户机聊天消息应用程序作为一个实验，以获得一些java socket方面的知识和经验。我一直在发送和接收消息时遇到问题。我确实获得了一个连接，线程看起来好像正在运行，但它不会互相发送或接收消息。我不确定连接是否会在连接后自动关闭，但我知道我做错了什么，但我似乎找不到它。如果你能帮助我，那就太好了。代码如下

---

服务器：

public class ServerGUI extends JFrame implements KeyListener{
/**
 * 
 */
private static final long serialVersionUID = 1L;
/*private JButton sendButton = new JButton("send");
private JButton connectButton = new JButton("Connect");
private JButton disconnectButton = new JButton("Disconnect");*/
private JTextField textMessage = new JTextField();
private JLabel connectMessageLabel = new JLabel("Waiting for Client");
private JTextArea messageTextArea = new JTextArea();
private JPanel buttonPanel = new JPanel();
private JPanel messageLabelPanel = new JPanel();
private JPanel messageTextAreaPanel = new JPanel();
private JPanel content = new JPanel();
private static String thisName= "<Me> ";
private static String friendLabel= "<My Friend> ";
private static JFrame serverFrame = new JFrame();
private int port= 0;
private String clientMessage=null;
private String myMessage=null;
private ServerSocket listenSocket;
private Socket connection;
private InputStream inStream;
private DataInputStream inDataStream;
private OutputStream outStream;
private DataOutputStream outDataStream;
private Thread runChatServer;

//----------------------------------------------------------------------------------------------
//-------------------------serverGui------------------------------------------------------------
@SuppressWarnings("deprecation")
public ServerGUI(int port){
    this.port = port;
    messageLabelPanel.setLayout(new GridLayout(1, 1, 1, 1));
    messageLabelPanel.add(connectMessageLabel);
    buttonPanel.setLayout(new GridLayout(1, 1, 1, 1));
    //buttonPanel.add(connectButton);
    //buttonPanel.add(sendButton);
    buttonPanel.add(textMessage);
    textMessage.addKeyListener(this);
    textMessage.setForeground(Color.BLACK);
    messageTextAreaPanel.setLayout(new BorderLayout(1, 1));
    messageTextAreaPanel.add(buttonPanel, BorderLayout.SOUTH);
    messageTextAreaPanel.add(messageLabelPanel,BorderLayout.NORTH);
    messageTextAreaPanel.add(new JScrollPane(messageTextArea),BorderLayout.CENTER);
    messageTextArea.setDisabledTextColor(Color.BLACK);
    messageTextArea.enable(false);
    content.setLayout(new GridLayout(1, 1, 1, 1));
    content.add(messageTextAreaPanel);
    content.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
    serverFrame.setContentPane(content);
    serverFrame.pack();
    serverFrame.setSize(450,550);
    serverFrame.setLocationRelativeTo(null);
    serverFrame.setVisible(true);
    serverFrame.setTitle("Chat Server");
    serverFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    startServer();
}

//-----------------------------------------------------------------------------------------------------
//-------------------------------keyPressed------------------------------------------------------------
public void startServer(){
    System.out.println("startServer");
    try{
        listenSocket = new ServerSocket(port);
        System.out.println("Waiting for client");
        connection = listenSocket.accept();
        System.out.println("Client Found");
        connectMessageLabel.setText("Client Found");
        runChatServer = new Thread(serverListeningAndChatting);
        runChatServer.start();
    }
    catch (Exception ex){

        System.out.println("No Connection Found");
        connectMessageLabel.setText("No Connection Found");
    }
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------listening------------------------------------------------------------
public void listening(){
    System.out.println("listening");
    try{
        inStream = connection.getInputStream();
        inDataStream = new DataInputStream(inStream);
        clientMessage = inDataStream.readUTF();
        if (clientMessage!= null){
            messageTextArea.append(clientMessage + "\n");
            clientMessage = null;
        }
    }catch(Exception ex){System.out.println(ex);}
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------sendMessage------------------------------------------------------------
public void sendMessage(){
    System.out.println("sendMessage");
    try{
        outStream = connection.getOutputStream();
        outDataStream = new DataOutputStream(outStream);

        if (myMessage!=null){
            outDataStream.writeUTF(myMessage);
            myMessage=null;
        }
    }catch(Exception ex){System.out.println("Message Failed");}
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------keyPressed------------------------------------------------------------
public void keyPressed(KeyEvent e) {
    if(e.getKeyChar() == KeyEvent.VK_ENTER){
        myMessage = friendLabel+ textMessage.getText();
        messageTextArea.append(thisName+textMessage.getText() +"\n");
        textMessage.setText("");
    }
}
public void keyReleased(KeyEvent e) {}
public void keyTyped(KeyEvent e) {}

//-----------------------------------------------------------------------------------------------------
//-------------------------------main------------------------------------------------------------
public static void main (String args[]){
    new ServerGUI(8901);
}

//-----------------------------------------------------------------------------------------------------
//-------------------------------run------------------------------------------------------------
public Runnable serverListeningAndChatting = new Runnable(){
    public void run() {
        while (true){
            System.out.println("Running");
            listening();
            sendMessage();
        }
    }
};

}

公共类ServerGUI扩展JFrame实现KeyListener{
/**
* 
*/
私有静态最终长serialVersionUID=1L；
/*私有JButton sendButton=新JButton（“发送”）；
私有JButton connectButton=新JButton（“连接”）；
专用JButton disconnectButton=新JButton（“断开”）*/
私有JTextField textMessage=新JTextField（）；
私有JLabel connectMessageLabel=新JLabel（“等待客户端”）；
私有JTextArea messageTextArea=新JTextArea（）；
private JPanel buttonPanel=new JPanel（）；
private JPanel messageLabelPanel=new JPanel（）；
private JPanel messageTextAreaPanel=new JPanel（）；
private JPanel content=new JPanel（）；
私有静态字符串thisName=“”；
私有静态字符串friendLabel=“”；
私有静态JFrame serverFrame=新JFrame（）；
专用int端口=0；
私有字符串clientMessage=null；
私有字符串myMessage=null；
私有服务器套接字listenSocket；
专用插座连接；
流内私有输入流；
私有数据输入流inDataStream；
私有输出流外流；
私有数据输出流outDataStream；
私有线程运行服务器；
//----------------------------------------------------------------------------------------------
//-------------------------serverGui------------------------------------------------------------
@抑制警告（“弃用”）
公共服务器GUI（int端口）{
this.port=端口；
setLayout（新的GridLayout（1,1,1,1））；
messageLabelPanel.add（connectMessageLabel）；
buttonPanel.setLayout（新的GridLayout（1,1,1,1））；
//按钮面板。添加（连接按钮）；
//按钮面板。添加（发送按钮）；
按钮面板添加（文本消息）；
textMessage.addKeyListener（这个）；
设置前景（颜色为黑色）；
messageTextAreaPanel.setLayout（新的BorderLayout（1,1））；
messageTextAreaPanel.add（按钮面板，BorderLayout.SOUTH）；
添加（messageLabelPanel，BorderLayout.NORTH）；
添加（新的JScrollPane（messageTextArea），BorderLayout.CENTER）；
messageTextArea.setDisabledTextColor（Color.BLACK）；
messageTextArea.enable（false）；
setLayout（新的GridLayout（1,1,1,1））；
content.add（messageTextAreaPanel）；
content.setboorder（BorderFactory.createEmptyBorder（10,10,10,10））；
setContentPane（内容）；
serverFrame.pack（）；
serverFrame.setSize（450550）；
serverFrame.setLocationRelativeTo（空）；
setVisible（true）；
setTitle（“聊天服务器”）；
serverFrame.setDefaultCloseOperation（JFrame.EXIT_ON_CLOSE）；
startServer（）；
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------按键------------------------------------------------------------
public void startServer（）{
System.out.println（“startServer”）；
试一试{
listenSocket=新服务器套接字（端口）；
System.out.println（“等待客户”）；
connection=listenSocket.accept（）；
System.out.println（“找到客户”）；
connectMessageLabel.setText（“找到的客户端”）；
runChatServer=新线程（serverlisteningandchating）；
runChatServer.start（）；
}
捕获（例外情况除外）{
System.out.println（“未找到连接”）；
connectMessageLabel.setText（“未找到连接”）；
}
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------倾听------------------------------------------------------------
公开聆听{
System.out.println（“侦听”）；
试一试{
inStream=connection.getInputStream（）；
inDataStream=新数据输入流（流内）；
clientMessage=inDataStream.readUTF（）；
if（clientMessage！=null）{
messageTextArea.append（clientMessage+“\n”）；
clientMessage=null；
}
}catch（异常ex）{System.out.println（ex）；}
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------发送消息------------------------------------------------------------
公共无效发送消息（）{
System.out.println（“发送消息”）；
试一试{
outStream=connection.getOutputStream（）；
outDataStream=新的DataOutputStream（扩展流）；
if（myMessage！=null）{
writeUTF（myMessage）；
myMessage=null；
}
}catch（异常ex）{System.out.println（“消息失败”）；}
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------按键------------------------------------------------------------
按下公共无效键（按键事件e）{
如果（例如getKeyChar（）==KeyEvent.VK_ENTER）{
myMessage=friendLabel+textMessage.getText（）；
messageTextArea.append（thisName+textMessage.getText（）+“\n”）；
textMessage.setText（“”）；
}
}
public void keyReleased（KeyEvent e）{}
public void keyTyped（KeyEvent e）{}
//-----------------------------------------------------------------------------------------------------
//-------------------------------主要------------------------------------------------------------
公共静态void main（字符串参数[]）{
新服务器GUI（8901）；
}
//---------------------------------------------------------------------
public class ClientGUI extends JFrame implements KeyListener{
/**
 * 
 */
private static final long serialVersionUID = 1L;
private JTextField textMessage = new JTextField();
private JLabel connectMessageLabel = new JLabel("Connection failed or no Server is available");
private JTextArea messageTextArea = new JTextArea();
private JPanel buttonPanel = new JPanel();
private JPanel messageLabelPanel = new JPanel();
private JPanel messageTextAreaPanel = new JPanel();
private JPanel content = new JPanel();
private static String thisName= "<Me> ";
private static String friendLabel= "<My Friend> ";
private static JFrame clientFrame = new JFrame();
private int port =0;
private String remoteMachine =null;
private String clientMessage=null;
private String myMessage=null;
private Socket connection;
private InputStream inStream;
private DataInputStream inDataStream;
private OutputStream outStream;
private DataOutputStream outDataStream;
private Thread runChatClient;
//-----------------------------------------------------------------------------------------------------
//-------------------------------ClientGUI------------------------------------------------------------

@SuppressWarnings("deprecation")
public ClientGUI(String remoteMachine, int port){
    this.port= port;
    this.remoteMachine = remoteMachine;
    messageLabelPanel.setLayout(new GridLayout(1, 1, 1, 1));
    messageLabelPanel.add(connectMessageLabel);
    buttonPanel.setLayout(new GridLayout(1, 1, 1, 1));
    //buttonPanel.add(connectButton);
    //buttonPanel.add(sendButton);
    buttonPanel.add(textMessage);
    textMessage.addKeyListener(this);
    textMessage.setForeground(Color.BLACK);
    messageTextAreaPanel.setLayout(new BorderLayout(1, 1));
    messageTextAreaPanel.add(buttonPanel, BorderLayout.SOUTH);
    messageTextAreaPanel.add(messageLabelPanel,BorderLayout.NORTH);
    messageTextAreaPanel.add(new JScrollPane(messageTextArea),BorderLayout.CENTER);
    messageTextArea.setDisabledTextColor(Color.BLACK);
    messageTextArea.enable(false);
    content.setLayout(new GridLayout(1, 1, 1, 1));
    content.add(messageTextAreaPanel);
    content.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
    clientFrame.setContentPane(content);
    clientFrame.pack();
    clientFrame.setSize(450,550);
    clientFrame.setLocationRelativeTo(null);
    clientFrame.setVisible(true);
    clientFrame.setTitle("Chat Client");
    clientFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    startClient();

}

//-----------------------------------------------------------------------------------------------------
//-------------------------------startClient------------------------------------------------------------
public void startClient(){
    System.out.println("startClient");
    try{
        System.out.println("Connecting to Server");
        connection = new Socket(remoteMachine, port);
        System.out.println("Server Found");
        connectMessageLabel.setText("Server Found");
        runChatClient = new Thread(clientListeningAndChatting);
        runChatClient.start();
    }
    catch (Exception ex){
        System.out.println("No Connection Found");
        connectMessageLabel.setText("No Connection Found");
    }

}
//-----------------------------------------------------------------------------------------------------
//-------------------------------keyPressed------------------------------------------------------------
public void keyPressed(KeyEvent e) {
    if(e.getKeyChar() == KeyEvent.VK_ENTER){
        myMessage = friendLabel+ textMessage.getText();
        messageTextArea.append(thisName+textMessage.getText() +"\n");
        textMessage.setText("");
    }
}

//-----------------------------------------------------------------------------------------------------
//-------------------------------listening------------------------------------------------------------
public void listening(){
    System.out.println("listening");
    try{
        inStream = connection.getInputStream();
        inDataStream = new DataInputStream(inStream);
        clientMessage = inDataStream.readUTF();
        if (clientMessage!= null){
            messageTextArea.append(clientMessage + "\n");
            clientMessage = null;
        }
    }catch(Exception ex){System.out.println("Disconnected");}
}
//-----------------------------------------------------------------------------------------------------
//-------------------------------sendMessage------------------------------------------------------------
public void sendMessage(){
    System.out.println("sendMessage");
    try{
        outStream = connection.getOutputStream();
        outDataStream = new DataOutputStream(outStream);
        if (myMessage!=null){
            outDataStream.writeUTF(myMessage);
            myMessage=null;
        }
    }catch(Exception ex){System.out.println("Message Failed");}
}
public void keyReleased(KeyEvent e) {}
public void keyTyped(KeyEvent e) {}
//-----------------------------------------------------------------------------------------------------
//-------------------------------main------------------------------------------------------------
public static void main (String args[]){
    new ClientGUI(null, 8901);
}

//-----------------------------------------------------------------------------------------------------
//-------------------------------run------------------------------------------------------------
public Runnable clientListeningAndChatting = new Runnable(){

    public void run() {
        System.out.println("Running");
        while (true){
            listening();
            sendMessage();
        }
    }
};
}

listenSocket.accept();