ServerApplication
package simplechatting.server;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
import lombok.Data;
@Data
class ConnectedSocket extends Thread{
private static List<ConnectedSocket> socketList = new ArrayList<>();
private Socket socket;
private InputStream inputStream;
private OutputStream outputStream;
private String username;
public ConnectedSocket(Socket socket) {
this.socket = socket;
socketList.add(this);
}
@Override
public void run() {
try {
outputStream = socket.getOutputStream();
PrintWriter out = new PrintWriter(outputStream,true);
out.println("join"); //client에게 전달
inputStream = socket.getInputStream(); // 들어올 문을 열어줌
BufferedReader in = new BufferedReader(new InputStreamReader(inputStream));
username = in.readLine();
System.out.println(username + "님이 접속하였습니다."); //server console 창
String userListStr = "";
for(int i = 0; i<socketList.size(); i++) {
userListStr += socketList.get(i).getUsername();
if(i < socketList.size() - 1 ) { // Last Index가 아니면,
userListStr += ",";
}
}
for(ConnectedSocket connectedSocket : socketList) {
outputStream = connectedSocket.getSocket().getOutputStream();
out = new PrintWriter(outputStream, true);
out.println("@welcome/" + username + "님이 접속하였습니다."); //클라이언트에게 돌려주는 용도
out.println("@userList/" + userListStr);
}
while(true) { //서버 안꺼지게 하는 용도
String message = in.readLine();
for(ConnectedSocket connectedSocket : socketList) {
outputStream = connectedSocket.getSocket().getOutputStream();
out = new PrintWriter(outputStream,true);
out.println(message);
}
}
}catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public class ServerApplication {
public static void main(String[] args) {
ServerSocket serverSocket = null;
try {
serverSocket = new ServerSocket(9090);
System.out.println("====<<< 서버 실행 >>>====");
while(true) {
Socket socket = serverSocket.accept(); // 클라이언트의 접속을 기다리는 녀석 // 연결버튼 누를때 까지
ConnectedSocket connectedSocket = new ConnectedSocket(socket);
connectedSocket.start();
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {
if(serverSocket != null) {
try {
serverSocket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
System.out.println("====<<< 서버 종료 >>>====");
}
}
}
ChattingClient
package simplechatting.client;
import java.awt.EventQueue;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ConnectException;
import java.net.Socket;
import java.net.UnknownHostException;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.border.EmptyBorder;
public class ChattingClient extends JFrame {
private Socket socket;
private String username;
private JPanel contentPane;
private JTextField ipInput;
private JTextField portInput;
private JTextArea contentView;
private JTextField messageInput;
private JList userList;
private DefaultListModel<String> userListModel;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
ChattingClient frame = new ChattingClient();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public ChattingClient() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 587, 444);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
ipInput = new JTextField();
ipInput.setText("127.0.0.1");
ipInput.setBounds(337, 11, 97, 32);
contentPane.add(ipInput);
ipInput.setColumns(10);
JButton connectButton = new JButton("연결");
connectButton.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
String ip = null; // 텍스트 필드에 있는 값을 가져옴
int port = 0; // 텍스트 필드에 있는 값을 가져옴
ip = ipInput.getText();
port = Integer.parseInt(portInput.getText());
try {
socket = new Socket(ip, port); //client → server단의 serverSocket.accept(); 에게 전달 →
JOptionPane.showMessageDialog(null,
socket.getInetAddress().toString().replaceAll("/", "") + "서버 접속" ,
"접속성공",
JOptionPane.INFORMATION_MESSAGE);
InputStream inputStream = socket.getInputStream(); // 서버로부터 올 메시지 통로를 열어줌
BufferedReader in = new BufferedReader(new InputStreamReader(inputStream));
if(in.readLine().equals("join")) {
username = JOptionPane.showInputDialog(null,
"사용자 이름을 입력하세요.",JOptionPane.INFORMATION_MESSAGE);
OutputStream outputStream = socket.getOutputStream(); // 서버에게 갈 통로를 열어줌
PrintWriter out = new PrintWriter(outputStream,true);
out.println(username); // 서버로 전달
}
Thread thread = new Thread(() ->{
try {
InputStream input = socket.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
while(true) {
String message = reader.readLine();
if(message.startsWith("@welcome")) {
int tokenIndex = message.indexOf("/"); // '/' ← token
message = message.substring(tokenIndex + 1);
}else if(message.startsWith("@userList")) {
int tokenIndex = message.indexOf("/");
message = message.substring(tokenIndex + 1);
String[] usernames = message.split(",");
userListModel.clear();
for(String username : usernames) {
userListModel.addElement(username);
}
continue;
}
contentView.append(message + "\n");
messageInput.setText("");
}
} catch (IOException e1) {
e1.printStackTrace();
}
});
thread.start();
}catch (ConnectException e1) {
JOptionPane.showMessageDialog(null,
"서버 접속 실패" ,
"접속실패",
JOptionPane.ERROR_MESSAGE);
}catch (UnknownHostException e1) {
e1.printStackTrace();
}catch (IOException e1) {
e1.printStackTrace();
}
}
});
connectButton.setBounds(501, 10, 65, 33);
contentPane.add(connectButton);
portInput = new JTextField();
portInput.setText("9090");
portInput.setBounds(446, 11, 43, 32);
contentPane.add(portInput);
portInput.setColumns(10);
JScrollPane contentScroll = new JScrollPane();
contentScroll.setBounds(12, 10, 313, 358);
contentPane.add(contentScroll);
contentView = new JTextArea();
contentScroll.setViewportView(contentView);
JScrollPane userListScroll = new JScrollPane();
userListScroll.setBounds(337, 53, 222, 315);
contentPane.add(userListScroll);
userListModel = new DefaultListModel<>();
userList = new JList(userListModel);
userListScroll.setViewportView(userList);
JScrollPane messageScroll = new JScrollPane();
messageScroll.setBounds(12, 378, 488, 23);
contentPane.add(messageScroll);
messageInput = new JTextField();
messageInput.addKeyListener(new KeyAdapter() {
@Override
public void keyPressed(KeyEvent e) {
if(e.getKeyCode() == KeyEvent.VK_ENTER) {
if(!messageInput.getText().isBlank()) {
try {
OutputStream outputStream = socket.getOutputStream(); // 소켓안에 outputStream 들어있음
PrintWriter out = new PrintWriter(outputStream,true);
out.println(username + ": " + messageInput.getText());
messageInput.setText("");
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} //
}
}
}
});
messageScroll.setViewportView(messageInput);
JButton sendButton = new JButton("전송");
sendButton.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
if(!messageInput.getText().isBlank()) {
try {
OutputStream outputStream = socket.getOutputStream(); // 소켓안에 outputStream 들어있음
PrintWriter out = new PrintWriter(outputStream,true);
out.println(username + ": " + messageInput.getText());
messageInput.setText("");
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} //
}
}
});
sendButton.setBounds(505, 378, 61, 23);
contentPane.add(sendButton);
}
}
UI 화면
HW + SW = 1