Question

我真的在网上搜索但我找不到我想要的东西。

我有2个类，分别是Clint和Server。这种联系在当地有效。

我想通过网络连接不同的PC。

示例：我的笔记本电脑将是服务器而我的朋友笔记本电脑将成为客户端。但我们不是同一个城市。所以我们必须使用互联网。

以下是代码：（Client.java中构造函数（host）的参数是127.0.0.1）

Client.java：

    public class Client extends JFrame{

    private JTextField userText;
    private JTextArea chatWindow;
    private ObjectOutputStream output;
    private ObjectInputStream input;
    private String message = "";
    private String serverIP;
    private Socket connection;

    //constructor
    public Client(String host) {
        super("Gulum Client");
        serverIP = host;
        userText = new JTextField();
        userText.setEditable(false);
        userText.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent event) {
                sendMessage(event.getActionCommand());
                userText.setText("");
            }
        });
        add(userText,BorderLayout.NORTH);
        chatWindow = new JTextArea();
        add(new JScrollPane(chatWindow),BorderLayout.CENTER);
        setSize(300,150);
        setVisible(true);

    }

    //connect to server
    public void startRunning(){
        try{
            connectToServer();
            setupStreams();
            whileChatting();
        }catch(EOFException eofException){
            showMessage("\n Client terminated connection");
        }catch(IOException ioexception){
            ioexception.printStackTrace();
        }finally{
            closeCrap();
        }
    }


    //connect to server
    private void connectToServer()throws IOException{
        showMessage("Attempting connection... \n");
        connection = new Socket(InetAddress.getByName(serverIP),6789);
        showMessage("Connected to: "+ connection.getInetAddress().getHostName());
    }

    //setup stream and recieve messages
    private void setupStreams() throws IOException{
        output = new ObjectOutputStream(connection.getOutputStream());
        output.flush();
        input = new ObjectInputStream(connection.getInputStream());
        showMessage("\n Streams are now setup. \n");
    }

    //while chatting with server
    private void whileChatting()throws IOException{
        ableToType(true);
        do{
            try{
                message = (String)input.readObject();
                showMessage("\n " + message );
            }catch(ClassNotFoundException classNotFounException){
                showMessage("\n Unknown that object type!");
            }
        }while(!message.equals("SERVER - END"));
    }

    //close the streams and socets
    private void closeCrap(){
        showMessage("\n Closing connections... ");
        ableToType(false);
        try{
            output.close();
            input.close();
            connection.close();
        }catch(IOException ioException){
            ioException.printStackTrace();
        }
    }

    //send messages to server
    private void sendMessage(String message){
        try{
            output.writeObject("CLIENT - " + message);
            output.flush();
            showMessage("\n CLIENT - " + message);
        }catch(IOException ioException){
            chatWindow.append("\n Stopped to sending message!");
        }
    }

    //change or update chatWindow
    private void showMessage(final String m){
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                chatWindow.append(m);
            }
        });
    }

    //gives user permisson to type crap into text box
    private void ableToType(final boolean tof){
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                userText.setEditable(tof);
            }
        });
    }

}

Server.java：

public class Server extends JFrame{

private JTextField userText;
private JTextArea chatWindow;
private ObjectOutputStream output;
private ObjectInputStream input;
private ServerSocket server;
private Socket connection;

public Server(){
    super("Gulum Instant Messenger");
    userText = new JTextField();
    userText.setEditable(false);
    userText.addActionListener(new ActionListener() {
        @Override
        public void actionPerformed(ActionEvent event) {
            sendMessage(event.getActionCommand());
            userText.setText("");
        }
    });
    add(userText,BorderLayout.NORTH);
    chatWindow = new JTextArea();
    add(new JScrollPane(chatWindow));
    setSize(300,150);
    setVisible(true);

}
//set up and run server
public void startRunning(){
    try{
        server = new ServerSocket(6789, 100);
        while(true){
            try{
                //connect and have conversation
                waitForConnection();
                setupStreams();
                whileChatting();
            }catch(EOFException eofException){
                showMessage("\n Server ended the connection! ");
            }finally{
                closeCrap();
            }
        }
    }catch(IOException ioException){
        ioException.printStackTrace();
    }
}

//wait for connection, then display information
private void waitForConnection()throws IOException{
    showMessage(" Waiting for someone to connetc... \n");
    connection = server.accept();
    showMessage(" Now connected to " + connection.getInetAddress().getHostName());

}

//get stream to send and recieve data
private void setupStreams()throws IOException{
    output = new ObjectOutputStream(connection.getOutputStream());
    output.flush();
    input = new ObjectInputStream(connection.getInputStream());
    showMessage("\n Streams are now setup! \n");
}

//during the chat conversation
private void whileChatting()throws IOException{
    String message = "You are now connected! ";
    sendMessage(message);
    ableToType(true);
    do{
        //have conversation
        try{
            message = (String) input.readObject();
            showMessage("\n"+message);
        }catch(ClassNotFoundException classNotFoundException){
            showMessage("\n idk wtf that user sent");
        }
    }while(!message.equals("CLIENT - END"));

}
//close streams and sockets after you are done
private void closeCrap(){
    showMessage("\n Closing connections... \n");
    ableToType(false);
    try{
        output.close();
        input.close();
        connection.close();
    }catch(IOException ioException){
        ioException.printStackTrace();
    }
}

//send a message to client
private void sendMessage(String message){
    try{
        output.writeObject(" SERVER - " + message);
        output.flush();
        showMessage("\n SERVER - " + message);
    }catch(IOException ioException){
        chatWindow.append("\n ERROR: THAT MESSAGE IS NOT SENT!!!");
    }

}
//update chat window
private void showMessage( final String text){
    SwingUtilities.invokeLater(new Runnable() {
        @Override
        public void run() {
            chatWindow.append(text);
        }
    });
}

//let user type stuff into their box
private void ableToType(final boolean tof){
    SwingUtilities.invokeLater(new Runnable() {
        @Override
        public void run() {
            userText.setEditable(tof);
        }
    });
}

}

Answer 1

您和您的朋友需要通过面向公众的IP访问彼此的计算机。如果您的每台计算机都在家庭路由器后面划分子网，则可能难以实现此目的。

我建议设置一个VPN。

以下是关于VPN的优秀文章：http://lifehacker.com/5940565/why-you-should-start-using-a-vpn-and-how-to-choose-the-best-one-for-your-needs

java中的在线即时通讯工具

1 个答案: