2024-09-05



import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.handler.TextWebSocketHandler;
 
public class MyWebSocketHandler extends TextWebSocketHandler {
 
    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        System.out.println("Connected ... " + session.getId());
    }
 
    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
        System.out.println("Received message: " + message.getPayload());
        // 发送消息回客户端
        session.sendMessage(new TextMessage("Hello, client!"));
    }
 
    @Override
    public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
        System.out.println("Transport error " + session.getId() + ":" + exception.getMessage());
    }
 
    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception {
        System.out.println("Connection closed " + session.getId());
    }
}

这段代码定义了一个MyWebSocketHandler类,它继承自TextWebSocketHandler。在这个类中,我们覆盖了四个方法:afterConnectionEstablishedhandleTextMessagehandleTransportErrorafterConnectionClosed。这些方法分别在WebSocket连接建立、接收消息、传输发生错误和连接关闭时被调用。在handleTextMessage方法中,我们接收到消息后,向客户端发送了一个问候消息。这个例子展示了如何在WebSocket连接中使用Spring Boot处理文本消息。

2024-09-05



import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.simp.config.ChannelRegistration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.messaging.simp.stomp.StompCommand;
import org.springframework.messaging.simp.stomp.StompHeaderAccessor;
import org.springframework.messaging.support.ChannelInterceptor;
import org.springframework.messaging.support.MessageHeaderAccessor;
import org.springframework.security.core.Authentication;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
 
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
 
    @Override
    public void configureMessageBroker(MessageBrokerRegistry config) {
        config.enableStompBrokerRelay("/topic")
              .setRelayHost("localhost")
              .setRelayPort(61613)
              .setClientLogin("guest")
              .setClientPasscode("guest");
        config.setApplicationDestinationPrefixes("/app");
        config.setUserDestinationPrefix("/user");
    }
 
    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/ws").withSockJS();
    }
 
    @Override
    public void configureClientInboundChannel(ChannelRegistration registration) {
        registration.interceptors(new ChannelInterceptor() {
            @Override
            public Message<?> preSend(Message<?> message, MessageChannel channel) {
                StompHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(message, StompHeaderAccessor.class);
                if (StompComm
2024-09-05

在Spring Boot中实现WebSocket功能,你可以使用Spring的@EnableWebSocketMessageBroker注解来配置一个WebSocket消息代理。以下是一个简单的例子:

  1. 添加Maven依赖:



<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
  1. 配置WebSocketMessageBroker:



import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
 
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
    
    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/ws").withSockJS();
    }
 
    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/topic");
        registry.setApplicationDestinationPrefixes("/app");
    }
}
  1. 创建控制器来处理WebSocket消息:



import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
 
@Controller
public class WebSocketController {
 
    @MessageMapping("/hello")
    @SendTo("/topic/greetings")
    public String greeting(String message) {
        return "Hello, " + message + "!";
    }
}
  1. 在前端使用WebSocket:



<script src="https://cdn.jsdelivr.net/npm/sockjs-client@1.7.0/dist/sockjs.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/stompjs@2.3.3/stomp.min.js"></script>
<script type="text/javascript">
    var socket = new WebSocket('ws://' + window.location.host + '/ws');
    var stompClient = Stomp.over(socket);
    stompClient.connect({}, function(frame) {
        console.log('Connected: ' + frame);
        stompClient.subscribe('/topic/gr
2024-09-05

在Django Channels中,WebSocket的工作原理如下:

  1. 用户通过HTTP请求连接到你的WebSocket服务。
  2. 服务器接收连接请求,建立WebSocket连接。
  3. 服务器和客户端之间可以双向发送消息。
  4. 连接可以在任何时候被任何一方关闭。

以下是一个简单的示例,展示了如何在Django Channels中使用WebSocket:




# consumers.py
 
from channels.generic.websocket import WebsocketConsumer
 
class ChatConsumer(WebsocketConsumer):
    def connect(self):
        # 当WebSocket连接建立时调用
        self.accept()
 
    def receive(self, text_data=None, bytes_data=None):
        # 当接收到消息时调用
        message = text_data
        # 对message进行处理,例如广播到所有连接的客户端
 
    def disconnect(self, close_code):
        # 当连接关闭时调用
        pass

在这个示例中,我们定义了一个名为ChatConsumer的WebSocket consumer类。当客户端连接到这个consumer时,connect方法被调用,并通过self.accept()来接受连接。当客户端发送消息时,receive方法被调用,并接收到的消息可以在这里处理。当连接关闭时,disconnect方法被调用。

routing.py中,你需要将这个consumer配置为可以处理WebSocket连接的路由:




# routing.py
 
from django.urls import path
from .consumers import ChatConsumer
 
websocket_urlpatterns = [
    path('ws/chat/', ChatConsumer.as_asgi()),
]

确保在你的Django项目中启用了Channels,并且正确配置了路由,这样你就可以在你的Django应用中使用WebSocket了。

2024-09-05



import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;
 
@ServerEndpoint("/websocket")
public class WebSocketTest {
    private static final CopyOnWriteArraySet<Session> sessions = new CopyOnWriteArraySet<>();
 
    @OnOpen
    public void onOpen(Session session) {
        sessions.add(session);
        System.out.println("Connected ... " + session.getId());
    }
 
    @OnClose
    public void onClose(Session session) {
        sessions.remove(session);
        System.out.println("Disconnected ... " + session.getId());
    }
 
    @OnError
    public void onError(Session session, Throwable throwable) {
        System.out.println("Error ... " + session.getId());
        throwable.printStackTrace();
    }
 
    @OnMessage
    public void onMessage(String message, Session session) {
        System.out.println("Received message ... " + session.getId() + " " + message);
        for (Session peer : sessions) {
            if (!peer.equals(session)) {
                try {
                    peer.getBasicRemote().sendText(message);
                } catch (IOException e) {
                    onError(peer, e);
                }
            }
        }
    }
}

这段代码使用Java定义了一个简单的WebSocket服务端点,它可以处理多个客户端的连接,并将接收到的消息广播到所有其他的客户端。这个例子展示了如何使用Java EE的WebSocket API,并且如何处理连接、消息接收、错误以及关闭事件。

2024-09-05

以下是一个使用Spring Boot整合WebSocket的简单示例。

首先,添加依赖到你的pom.xml文件:




<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>

然后,配置WebSocket:




import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
 
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
 
    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/ws").withSockJS();
    }
 
    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/topic");
        registry.setApplicationDestinationPrefixes("/app");
    }
}

接下来,创建一个控制器来处理WebSocket消息:




import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
 
@Controller
public class WebSocketController {
 
    @Autowired
    private SimpMessagingTemplate simpMessagingTemplate;
 
    @MessageMapping("/hello")
    @SendTo("/topic/greetings")
    public String greeting(String message) {
        return "Hello, " + message + "!";
    }
 
    @RequestMapping("/sendMessage")
    @ResponseBody
    public String sendMessage(String message) {
        simpMessagingTemplate.convertAndSend("/topic/greetings", "Hello, " + message + "!");
        return "Message sent";
    }
}

最后,在HTML页面中使用WebSocket:




<!DOCTYPE html>
<html>
<head>
    <title>WebSocket Test</title>
    <script src="https://cdn.jsdelivr.net/npm/sockjs-client@1.7.0/dist/sockjs.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/s
2024-09-05

在这个案例中,我们将实现WebSocket的处理器和初始化配置。




import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.websocketx.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
 
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
 
@Component
public class WebSocketHandler extends SimpleChannelInboundHandler<WebSocketFrame> {
 
    private static final Map<String, ChannelHandlerContext> clients = new ConcurrentHashMap<>();
 
    @Autowired
    private TextWebSocketHandler textWebSocketHandler;
 
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, WebSocketFrame frame) throws Exception {
        // 判断是否WebSocket握手请求
        if (frame instanceof FullHttpRequest) {
            handleHttpRequest(ctx, (FullHttpRequest) frame);
        } else if (frame instanceof CloseWebSocketFrame) {
            // 关闭WebSocket连接
            handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain());
        } else if (frame instanceof PingWebSocketFrame) {
            // 发送Pong消息
            ctx.channel().write(new PongWebSocketFrame(frame.content().retain()));
        } else if (frame instanceof TextWebSocketFrame) {
            // 处理文本消息
            String message = ((TextWebSocketFrame) frame).text();
            textWebSocketHandler.handleTextMessage(ctx, message);
        } else {
            throw new UnsupportedOperationException("Unsupported frame type: " + frame.getClass().getName());
        }
    }
 
    private void handleHttpRequest(ChannelHandlerContext ctx, FullHttpRequest req) {
        // 如果HTTP请求不是WebSocket握手请求,则返回HTTP响应
        if (!handshaker.isWebSocketUpgradeRequest(req)) {
            sendHttpResponse(ctx, req, new DefaultFullHttpResponse(req.protocolVersion(), HttpResponseStatus.BAD_REQUEST));
            return;
        }
 
        // 构造握手响应返回
        handshaker.handshake(ctx.channel(), req);
    }
 
    private void sendHttpResponse(ChannelHandlerContext ctx, FullHttpRequest req, DefaultFullHttpResponse res) {
        // 发送HTTP响应
        if (res.status().code() != 200) {
            ByteBuf byteBuf = Unpooled.copiedBuff
2024-09-04



import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.config.annotation.*;
 
@Configuration
@EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {
    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
        registry.addHandler(myHandler(), "/my-websocket-endpoint")
            .setAllowedOrigins("*");
    }
 
    @Bean
    public WebSocketHandler myHandler() {
        // 实现自定义的WebSocketHandler
        return new MyCustomWebSocketHandler();
    }
}

在这个例子中,我们定义了一个配置类WebSocketConfig,实现了WebSocketConfigurer接口。我们注册了一个名为/my-websocket-endpoint的WebSocket处理器,并且设置了允许来自任何源的连接(通常在生产环境中应当限制允许的源)。我们还定义了一个Bean方法myHandler()来提供我们自定义的WebSocket处理器MyCustomWebSocketHandler。这个处理器需要你自己实现org.springframework.web.socket.WebSocketHandler接口。

2024-09-04

在Spring Boot中集成WebSocket,你可以使用Spring的@EnableWebSocketMessageBroker注解来配置一个WebSocket消息代理。以下是一个简单的例子:

  1. 添加依赖到你的pom.xml



<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
  1. 配置WebSocketMessageBroker:



import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
 
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
    
    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/ws").withSockJS();
    }
 
    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/topic");
        registry.setApplicationDestinationPrefixes("/app");
    }
}
  1. 创建一个控制器来处理WebSocket消息:



import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
 
@Controller
public class WebSocketController {
 
    @MessageMapping("/hello")
    @SendTo("/topic/greetings")
    public String greeting(String message) {
        return "Hello, " + message + "!";
    }
}
  1. 前端使用SockJS和STOMP:



<script src="https://cdn.jsdelivr.net/npm/sockjs-client@1.7.0/dist/sockjs.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/stompjs@2.3.3/stomp.min.js"></script>
<script>
    var socket = new WebSocket('ws://localhost:8080/ws');
    var stompClient = Stomp.over(socket);
    stompClient.connect({}, function(frame) {
        console.log('Connected: ' + frame);
        stompClient.subscribe('/
2024-09-04



using System;
using System.Data.SQLite;
using System.Windows.Forms;
using WebSocket4Net;
 
public partial class MainForm : Form
{
    private WebSocket webSocket;
    private readonly string sqliteConnectionString = "Data Source=your_database_path;Version=3;";
 
    public MainForm()
    {
        InitializeComponent();
        InitializeWebSocket();
    }
 
    private void InitializeWebSocket()
    {
        webSocket = new WebSocket("ws://your_websocket_server_address");
        webSocket.Opened += WebSocket_Opened;
        webSocket.Closed += WebSocket_Closed;
        webSocket.MessageReceived += WebSocket_MessageReceived;
        webSocket.Error += WebSocket_Error;
    }
 
    private void StartButton_Click(object sender, EventArgs e)
    {
        webSocket.Open();
    }
 
    private void StopButton_Click(object sender, EventArgs e)
    {
        webSocket.Close();
    }
 
    private void WebSocket_Opened(object sender, EventArgs e)
    {
        // WebSocket连接打开时的操作
    }
 
    private void WebSocket_Closed(object sender, EventArgs e)
    {
        // WebSocket连接关闭时的操作
    }
 
    private void WebSocket_MessageReceived(object sender, MessageReceivedEventArgs e)
    {
        // 接收到消息时的操作
        var message = e.Message;
 
        // 将接收到的消息存储到SQLite数据库中
        using (var connection = new SQLiteConnection(sqliteConnectionString))
        {
            connection.Open();
            using (var command = connection.CreateCommand())
            {
                command.CommandText = "INSERT INTO your_table_name (column_name) VALUES (@message)";
                command.Parameters.AddWithValue("@message", message);
                command.ExecuteNonQuery();
            }
        }
    }
 
    private void WebSocket_Error(object sender, EventArgs e)
    {
        // 处理错误
    }
}

在这个代码实例中,我们创建了一个WebSocket客户端,并在连接打开、关闭以及接收到消息时的相关操作。我们还演示了如何将接收到的消息存储到SQLite数据库中。这个例子提供了一个简单的框架,可以根据实际需求进行扩展和定制。