Question

我创建了多聊天应用程序。

当前问题 当我将课程Chatinterface编译2次时，会打开2个客户端。现在当我尝试通过在文本区域中键入文本消息进行通信时。另一个客户端不显示消息，反之亦然。

有人可以更正我的代码吗？并告诉我发生了什么。

请不要苛刻我只是初学者。

请注意我已提供服务器代码以获取详细说明。

package stack;

import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextArea;
import javax.swing.SpringLayout;

class Chatinterface implements ActionListener,Runnable {

    private JFrame chatwindow;
    JTextArea typemsg;
    JTextArea displaymsg;
    JButton sendbutton;
    JButton logoutbutton;
    Socket client;
    BufferedReader read;
    PrintWriter write;
    String getmsg;
    String gettext;
    public Chatinterface(){

        try {
            client = new Socket("localhost",3420);
            write = new PrintWriter(client.getOutputStream());


        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        displaygui();
    }

    private void displaygui() {
        chatwindow = new JFrame();
        chatwindow.setResizable(false);
        chatwindow.setBounds(100, 100, 450, 300);
        chatwindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        SpringLayout springLayout = new SpringLayout();
        chatwindow.getContentPane().setLayout(springLayout);

        typemsg = new JTextArea();
        springLayout.putConstraint(SpringLayout.NORTH, typemsg, 171, SpringLayout.NORTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.WEST, typemsg, 10, SpringLayout.WEST, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.SOUTH, typemsg, -10, SpringLayout.SOUTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.EAST, typemsg, 340, SpringLayout.WEST, chatwindow.getContentPane());
        chatwindow.getContentPane().add(typemsg);

        displaymsg = new JTextArea();
        displaymsg.setWrapStyleWord(true);
        displaymsg.setEditable(false);
        springLayout.putConstraint(SpringLayout.NORTH, displaymsg, 10, SpringLayout.NORTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.WEST, displaymsg, 0, SpringLayout.WEST, typemsg);
        springLayout.putConstraint(SpringLayout.SOUTH, displaymsg, 160, SpringLayout.NORTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.EAST, displaymsg, 0, SpringLayout.EAST, typemsg);
        chatwindow.getContentPane().add(displaymsg);

        sendbutton = new JButton("Send");
        springLayout.putConstraint(SpringLayout.NORTH, sendbutton, -76, SpringLayout.SOUTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.WEST, sendbutton, 5, SpringLayout.EAST, typemsg);
        springLayout.putConstraint(SpringLayout.SOUTH, sendbutton, -27, SpringLayout.SOUTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.EAST, sendbutton, 82, SpringLayout.EAST, typemsg);
        chatwindow.getContentPane().add(sendbutton);
        sendbutton.addActionListener(this);
        sendbutton.setActionCommand("S");

        logoutbutton = new JButton("Logout");
        springLayout.putConstraint(SpringLayout.NORTH, logoutbutton, 50, SpringLayout.NORTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.WEST, logoutbutton, -65, SpringLayout.EAST, sendbutton);
        springLayout.putConstraint(SpringLayout.SOUTH, logoutbutton, 108, SpringLayout.NORTH, chatwindow.getContentPane());
        springLayout.putConstraint(SpringLayout.EAST, logoutbutton, 0, SpringLayout.EAST, sendbutton);
        chatwindow.getContentPane().add(logoutbutton);
        logoutbutton.addActionListener(this);
        logoutbutton.setActionCommand("L");
        chatwindow.setVisible(true);

    }
    public static void main(String args[])
    {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Chatinterface method = new Chatinterface();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
        Thread t1 = new Thread();
        t1.start();
    }

    @Override
    public void actionPerformed(ActionEvent arg0) {

        if(arg0.getActionCommand().equals("S"))
        {
            String gettext2;
            gettext2 = typemsg.getText();
            write.println(gettext2);
            displaymsg.append(gettext2+"\n");
            typemsg.setText("");
        }

        if(arg0.getActionCommand().equals("L")){
            System.exit(0);
        }

    }
    @Override
    public void run() {
        String readmsg;

        try {
            read = new BufferedReader(new InputStreamReader(client.getInputStream()));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        try {
            readmsg = read.readLine();

            while(readmsg!=null)
            {

                displaymsg.append(readmsg);

            }


        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
}

以下是每当连接新客户端时调用的类处理程序。

package stack;

import java.io.*;
import java.net.*;

public class Handler implements Runnable {
    Socket s;

    String getmsg = null;
    String sendmsg;

    public Handler(Socket s) {
        this.s = s;

    }
    public void run() {
            BufferedReader reader1 = null;
            PrintWriter writer1 = null;

            try {
                reader1 = new BufferedReader(new InputStreamReader(
                        s.getInputStream()));
                writer1 = new PrintWriter(s.getOutputStream(), true);
                sendmsg = reader1.readLine();
                while (sendmsg!=null) {

                        writer1.println(sendmsg);

                }
                reader1.close();
                writer1.close();
                s.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();

            }

    }
}

这是主服务器类

package stack;

import java.net.*;
public class Servera  {
    public static void main(String[] args) throws Exception {
        Socket s;
        ServerSocket server = new ServerSocket(3420);

        while(true)
        {
            s = server.accept();
            Handler handler1 = new Handler(s);
            Thread t1 = new Thread(handler1);
            t1.start();
        }

    }
}

Answer 1

您的服务器未收到客户端发送的消息。为此您需要使用 write.flush（）在客户端中刷新OutputStream 以下是代码更改：

   if(arg0.getActionCommand().equals("S"))
        {
            String gettext2;
            gettext2 = typemsg.getText();
            write.println(gettext2);
            write.flush()
            displaymsg.append(gettext2+"\n");
            typemsg.setText("");
        }

此外，您从一个客户端向另一个客户端发送消息的逻辑也不正确。根据您的代码，服务器会将消息发送到已收到消息的同一客户端。这需要维护客户端套接字池和然后将消息广播给所有客户。希望这些回答你的问题。如果正确，请接受答案。

客户端未在聊天应用程序中进行通信

1 个答案: