网络编程之简单的多人聊天程序

服务器端

package net;
import java.awt.*;
import java.io.*;
import java.net.*;
import java.util.*;
import java.util.List;

import javax.swing.*;
//服务器端程序
public class TCPServer extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
private ServerSocket ss = null;
private boolean bStart = false;

private JTextArea taContent = new JTextArea();

private int index = 0;

List<Client> clients = new ArrayList<Client>();

public void launchFrame() {
//Container con = this.getContentPane();
taContent.setEditable(false);
taContent.setBackground(Color.DARK_GRAY);
taContent.setForeground(Color.YELLOW);
this.add(taContent);
this.setSize(300, 350);
this.setLocation(400, 200);
this.setTitle("TCP Server");
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
tcpMonitor();//调用监听器方法
}
//监听器方法
public void tcpMonitor() {
try {
ss = new ServerSocket(8888);
bStart = true;
} catch (IOException e) {
e.printStackTrace();
}

try {
while (bStart) {
index++;
Socket s = ss.accept();
Client c = new Client(s);
clients.add(c);

taContent.append(s.getInetAddress().getHostAddress()
+ " connected " + index + " clients\n");
new Thread(c).start();

}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
ss.close();
} catch (IOException e) {

e.printStackTrace();
}
}

}

public static void main(String args[]) {
TCPServer ts = new TCPServer();
ts.launchFrame();
}

private class Client implements Runnable {
DataInputStream dis = null;
DataOutputStream dos = null;

Socket s = null;
boolean bStart = false;

Client(Socket s) {
this.s = s;
try {
dis = new DataInputStream(s.getInputStream());
dos = new DataOutputStream(s.getOutputStream());
} catch (IOException e) {
e.printStackTrace();
}

bStart = true;
}
//分发信息给每个客户端
public void sendToEveryClient(String str) {
try {
dos.writeUTF(str);
dos.flush();

} catch (IOException e) {
index--;
clients.remove(this);
taContent.append(s.getInetAddress().getHostAddress()
+ " exited " + index + " clients\n");
System.out.println("对方退出了！我从List里面去掉了！");
}
}

public void run() {
try {
while (bStart) {
String str = dis.readUTF();
System.out.println(str);
for (int i = 0; i < clients.size(); i++) {
Client c = clients.get(i);
c.sendToEveryClient(str);//群发消息当然要在循环 环境里
}
}
} catch (EOFException e) {
clients.remove(this);
taContent.append(s.getInetAddress().getHostAddress()
+ " exited " + clients.size() + " clients\n");
System.out.println("client closed");
} catch (SocketException e) {
System.out.println("client closed");
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (s != null)
s.close();
if (dis != null)
dis.close();
if (dos != null)
dos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

}

}


客户端
package net;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;

import javax.swing.*;

public class TCPClient extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
TextArea taContent = new TextArea();
JTextField tfTxt = new JTextField(20);

JButton send = new JButton("发送");
JButton connect = new JButton("连接");
JButton clear = new JButton("清空");

boolean live = false;
JPanel p1 = new JPanel();
JPanel p2 = new JPanel();

Socket s = null;
DataOutputStream dos = null;
DataInputStream dis = null;

boolean bConnected = false;

Thread t = new Thread(new RecToServer());

public void launchFrame() {

taContent.setEditable(false);

p2.setLayout(new FlowLayout(FlowLayout.CENTER, 10, 5));
p2.add(send);
p2.add(connect);
p2.add(clear);

Container con = this.getContentPane();

con.add(taContent, "North");
con.add(tfTxt, "Center");
con.add(p2, "South");

this.setSize(300, 350);
this.setLocation(400, 200);
this.setTitle("Chat Client");

this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

connect.addActionListener(new Connect());
send.addActionListener(new SendMsg());
clear.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
taContent.setText("");
}
});
}

public void connectToServer() {
try {

s = new Socket("127.0.0.1", 8888);
dos = new DataOutputStream(s.getOutputStream());
dis = new DataInputStream(s.getInputStream());

bConnected = true;

} catch (BindException e) {
System.out.println("找不到指定的服务器");
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

public void disConnect() {
try {
if (s != null) {
s.close();
}

if (dos != null) {
dos.close();
}
if (dis != null) {
dis.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}

public static void main(String args[]) {
TCPClient tc = new TCPClient();
tc.launchFrame();
}

private class Connect implements ActionListener {
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand() == "连接") {

connectToServer();
try {
t.start();
} catch (IllegalThreadStateException ex) {

}

connect.setText("断开连接");

} else if (e.getActionCommand() == "断开连接") {
disConnect();
connect.setText("连接");
}

}
}

private class SendMsg implements ActionListener {
public void actionPerformed(ActionEvent e) {
if (connect.getActionCommand() == "连接") {
JOptionPane.showMessageDialog(TCPClient.this,
"没有找到指定的服务器", "错误提示", 1);
} else {
String str = tfTxt.getText();
tfTxt.setText("");

try {
dos.writeUTF(str);
dos.flush();
} catch (SocketException ex) {
System.out.println("没有找到指定的服务器");
JOptionPane.showMessageDialog(TCPClient.this,
"没有找到指定的服务器", "错误提示", 1);
} catch (IOException ex) {
ex.printStackTrace();
}
}

}
}

private class RecToServer implements Runnable {
public void run() {
try {
while (bConnected) {
String str = dis.readUTF();
// System.out.println(str);

taContent.append(str + "\n");
}
} catch (SocketException e) {
System.out.println("服务器已关闭");
} catch (IOException e) {
e.printStackTrace();
}
}
}
}