Hỏi về socket trong java

#1

chào các a chị, em đang có 1 bài tập nhỏ về socket trong java, e đã tạo được 2 cửa sổ chat gồm Client và Sever có sử dụng socket. Khi chạy riêng trong cmd thì Client và Server kết nối và có thể gửi tin nhắn qua lại. Nhưng khi em tạo 1 button, khi ấn vào button đó thì sẽ chạy và hiển thị ra Client, nhưng Client đó lại không thể kết nối và gửi tin nhắn tới Server. Mọi người có thể chỉ cho e cách khắc phục được k ạ, em cảm ơn. Dưới đây là code ạ
GD
button.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */


/**
 *
 * @author Lenovo
 */
public class button extends javax.swing.JFrame {

    /**
     * Creates new form button
     */
    public button() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jButton1 = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jButton1.setText("jButton1");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        });

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, 400, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, 289, Short.MAX_VALUE)
                .addContainerGap())
        );

        pack();
    }// </editor-fold>                        

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
		chat_client b = new chat_client();
		b.setVisible(true) ;
    }                                        

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(button.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(button.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(button.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(button.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new button().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    // End of variables declaration                   
}

chat_client.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */



import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.net.ServerSocket;
import java.net.Socket;

/**
 *
 * @author mukul
 */
public class chat_client extends javax.swing.JFrame {
    static Socket s;
    static DataInputStream dis;
    static DataOutputStream dout;

    /**
     * Creates new form chat_client
     */
    public chat_client() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">//GEN-BEGIN:initComponents
    private void initComponents() {

        jScrollPane1 = new javax.swing.JScrollPane();
        msg_area = new javax.swing.JTextArea();
        msg_text = new javax.swing.JTextField();
        msg_send = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        msg_area.setColumns(20);
        msg_area.setRows(5);
        jScrollPane1.setViewportView(msg_area);

        msg_send.setText("send");
        msg_send.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                msg_sendActionPerformed(evt);
            }
        });

        jLabel1.setFont(new java.awt.Font("Tahoma", 1, 18)); // NOI18N
        jLabel1.setText("client");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jScrollPane1)
                    .addGroup(layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addGroup(layout.createSequentialGroup()
                                .addComponent(msg_text, javax.swing.GroupLayout.PREFERRED_SIZE, 316, javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                                .addComponent(msg_send))
                            .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 127, javax.swing.GroupLayout.PREFERRED_SIZE))
                        .addGap(0, 18, Short.MAX_VALUE)))
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 23, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 224, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(msg_text)
                    .addGroup(layout.createSequentialGroup()
                        .addComponent(msg_send)
                        .addGap(0, 2, Short.MAX_VALUE)))
                .addContainerGap())
        );

        pack();
    }// </editor-fold>//GEN-END:initComponents

    private void msg_sendActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_msg_sendActionPerformed
        // TODO add your handling code here:
        
         try{
        String msg="";
        msg=msg_text.getText();
        dout.writeUTF(msg);
        msg_text.setText("");
        }
        catch(Exception e)
        {
        //handle the exception here
        }
        
    }//GEN-LAST:event_msg_sendActionPerformed

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(chat_client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(chat_client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(chat_client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(chat_client.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new chat_client().setVisible(true);
            }
        });
        
         try {
            String msgin = "";
            
            s = new Socket("localhost",4444); // ip address is of localhost because server is running on the same mschine
            dis = new DataInputStream(s.getInputStream());
            dout = new DataOutputStream(s.getOutputStream());

            while (!msgin.equals("exit")) {
                msgin = dis.readUTF();
                msg_area.setText(msg_area.getText() + "\n Server : " + msgin);
            }

        } catch (Exception e) {
            //handle the exception here
        }

        
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JLabel jLabel1;
    private javax.swing.JScrollPane jScrollPane1;
    private static javax.swing.JTextArea msg_area;
    private javax.swing.JButton msg_send;
    private javax.swing.JTextField msg_text;
    // End of variables declaration//GEN-END:variables
}

chat_server.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */


import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.net.ServerSocket;
import java.net.Socket;

/**
 *
 * @author mukul
 */
public class chat_server extends javax.swing.JFrame {

    static ServerSocket ss;
    static Socket s;
    static DataInputStream dis;
    static DataOutputStream dout;

    /**
     * Creates new form chat_server
     */
    public chat_server() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">//GEN-BEGIN:initComponents
    private void initComponents() {

        jScrollPane1 = new javax.swing.JScrollPane();
        msg_area = new javax.swing.JTextArea();
        msg_text = new javax.swing.JTextField();
        msg_send = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        msg_area.setColumns(20);
        msg_area.setRows(5);
        jScrollPane1.setViewportView(msg_area);

        msg_send.setText("send");
        msg_send.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                msg_sendActionPerformed(evt);
            }
        });

        jLabel1.setFont(new java.awt.Font("Tahoma", 1, 18)); // NOI18N
        jLabel1.setText("Server");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jScrollPane1)
                    .addGroup(layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 114, javax.swing.GroupLayout.PREFERRED_SIZE)
                            .addGroup(layout.createSequentialGroup()
                                .addComponent(msg_text, javax.swing.GroupLayout.PREFERRED_SIZE, 303, javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                                .addComponent(msg_send)))
                        .addGap(0, 18, Short.MAX_VALUE)))
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 24, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 225, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(msg_text)
                    .addComponent(msg_send, javax.swing.GroupLayout.DEFAULT_SIZE, 28, Short.MAX_VALUE))
                .addContainerGap())
        );

        pack();
    }// </editor-fold>//GEN-END:initComponents

    private void msg_sendActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_msg_sendActionPerformed
        // TODO add your handling code here:
        
        try{
        String msg="";
        msg=msg_text.getText();
        dout.writeUTF(msg);
        msg_text.setText("");
        }
        catch(Exception e)
        {
        //handle the exception here
        }
        
        
    }//GEN-LAST:event_msg_sendActionPerformed

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(chat_server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(chat_server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(chat_server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(chat_server.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new chat_server().setVisible(true);
            }
        });

        try {
            String msgin = "";
            ss = new ServerSocket(4444);
            s = ss.accept();
            dis = new DataInputStream(s.getInputStream());
            dout = new DataOutputStream(s.getOutputStream());

            while (!msgin.equals("exit")) {
                msgin = dis.readUTF();
                msg_area.setText(msg_area.getText() + "\n Client : " + msgin);
            }

        } catch (Exception e) {
            //handle the exception here
        }

    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JLabel jLabel1;
    private javax.swing.JScrollPane jScrollPane1;
    private static javax.swing.JTextArea msg_area;
    private javax.swing.JButton msg_send;
    private javax.swing.JTextField msg_text;
    // End of variables declaration//GEN-END:variables
}
Lỗi mở cửa sổ không dừng (jframe)
#2

Khi bạn nhấn nút (button.java) thì bạn chỉ gọi đến hàm dựng của lớp chat_client chứ không phải phương thức main() của chat_client. Vì thế mà đoạn mã bạn kết nối Socket trong main() không được thực thi.

2 Likes
#3

(post withdrawn by author, will be automatically deleted in 24 hours unless flagged)

#4

(post withdrawn by author, will be automatically deleted in 24 hours unless flagged)

#5

vậy h gọi phương thức main() của chat_client thì dùng lệnh nào ạ ?

#6

Mình code một button, khi click vào button đó thì sẽ mở 1 jframe client, nhưng hiện tại khi click vào button thì client cứ hiện ra không ngừng. Có cách nào xử lý k ạ ?

#7

Bạn đăng cả code đoạn xử lý click lên đây

#9 
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    // TODO add your handling code here:
	chat_client b = new chat_client();
	b.setVisible(true) ;
}

đây bạn ơi, làm cách nào để gọi cả hàm main ra bây h bạn :(((( ?

#10

@jundo: bạn hỏi không đúng rồi.
Thứ bạn cần là khi gọi đến hàm dựng của chat_client thì đoạn mã khởi tạo kết nối sẽ được thực thi.

Nói thẳng ra: bạn làm sai khi để đoạn kết nối trong main(). Bạn có thể để nó trong hàm dựng của chat_client mà.

1 Like
83% thành viên diễn đàn không hỏi bài tập, còn bạn thì sao?