Java Websocketを使用してリアルタイムチャット機能を実装するにはどうすればよいですか?

import javax.websocket.*;
import java.net.URI;

@ClientEndpoint
public class ChatClient {

    private static final String SERVER_URI = "ws://localhost:8080/chat";

    private Session session;

    @OnOpen
    public void onOpen(Session session) {
        this.session = session;
    }

    @OnMessage
    public void onMessage(String message) {
        System.out.println("Received message: " + message);
    }

    public void sendMessage(String message) {
        session.getAsyncRemote().sendText(message);
    }

    public static void main(String[] args) throws Exception {
        WebSocketContainer container = ContainerProvider.getWebSocketContainer();
        URI uri = new URI(SERVER_URI);
        Session session = container.connectToServer(ChatClient.class, uri);
        ChatClient client = new ChatClient();
        client.onOpen(session);

        // 发送消息示例
        client.sendMessage("Hello, World!");

        // 关闭连接
        session.close();
    }
}

import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;

@ServerEndpoint("/chat")
public class ChatServer {

    @OnOpen
    public void onOpen(Session session) {
        System.out.println("Connection opened: " + session.getId());
    }

    @OnMessage
    public void onMessage(String message, Session session) {
        System.out.println("Received message: " + message);
        broadcast(message);
    }

    @OnClose
    public void onClose(Session session) {
        System.out.println("Connection closed: " + session.getId());
    }

    @OnError
    public void onError(Throwable t) {
        t.printStackTrace();
    }

    private static void broadcast(String message) {
        for (Session session : Session.getOpenSessions()) {
            session.getAsyncRemote().sendText(message);
        }
    }
}