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徐州网站开发如何,电子商务网站流程图,如何制作ppt视频教程,个人简介干净短句实现websocket的方式 1.springboot中有两种方式实现websocket#xff0c;一种是基于原生的基于注解的websocket#xff0c;另一种是基于spring封装后的WebSocketHandler 基于原生注解实现websocket 1#xff09;先引入websocket的starter坐标 dependencygrou…实现websocket的方式 1.springboot中有两种方式实现websocket一种是基于原生的基于注解的websocket另一种是基于spring封装后的WebSocketHandler 基于原生注解实现websocket 1先引入websocket的starter坐标 dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-websocket/artifactId/dependency2编写websocket的Endpoint端点类 ServerEndpoint(value /ws/{token}) Component public class WebsocketHandler2 {private final static Logger log LoggerFactory.getLogger(WebsocketHandler2.class);private static final SetSession SESSIONS new ConcurrentSkipListSet(Comparator.comparing(Session::getId));private static final ScheduledExecutorService scheduledExecutor Executors.newScheduledThreadPool(10);private static final MapString, ScheduledFuture? futures new ConcurrentHashMap();OnOpenpublic void onOpen(Session session, PathParam(token) String token, EndpointConfig config) throws IOException { // session.addMessageHandler(new PongHandler());ScheduledFuture? future scheduledExecutor.scheduleWithFixedDelay(() - sendPing(session), 5, 5, TimeUnit.SECONDS);String queryString session.getQueryString();futures.put(session.getId(), future);session.setMaxIdleTimeout(6 * 1000);SESSIONS.add(session);log.info(open connect sessionId{}, token{}, queryParam{}, session.getId(), token, queryString);String s String.format(ws client(id%s) has connected, session.getId());session.getBasicRemote().sendText(s);}static class PongHandler implements MessageHandler.WholePongMessage {Overridepublic void onMessage(PongMessage message) {ByteBuffer data message.getApplicationData();String s new String(data.array(), StandardCharsets.UTF_8);log.info(receive pong msg {}, s);}}OnClosepublic void onClose(Session session, CloseReason reason) {log.info(session(id{}) close ,closeCode{},closeParse{}, session.getId(), reason.getCloseCode(), reason.getReasonPhrase());SESSIONS.remove(session);ScheduledFuture? future futures.get(session.getId());if (future ! null) {future.cancel(true);}}OnMessagepublic void onMessage(String message, Session session) throws IOException {log.info(receive client(id{}) msg{}, session.getId(), message);String s String.format(reply your(id%s) msg【%s】, session.getId(), message);session.getBasicRemote().sendText(s);}OnMessagepublic void onPong(PongMessage message, Session session) throws IOException {ByteBuffer data message.getApplicationData();String s new String(data.array(), StandardCharsets.UTF_8);log.info(receive client(id{}) pong msg {}, session.getId(), s);}OnErrorpublic void onError(Session session, Throwable error) {log.error(Session(id{}) error occur , session.getId(), error);}private void sendPing(Session session) {if (session.isOpen()) {String replyContent String.format(Hello,client(id%s), session.getId());try {session.getBasicRemote().sendPing(ByteBuffer.wrap(replyContent.getBytes(StandardCharsets.UTF_8)));} catch (IOException e) {log.error(ping client(id{}) error, session.getId(), e);}return;}SESSIONS.remove(session);ScheduledFuture? future futures.remove(session.getId());if (future ! null) {future.cancel(true);}} }注解说明 ServerEndpoint标记这个是一个服务端的端点类 OnOpen 标记此方法是建立websocket连接时的回调方法 OnMessage 标记此方法是接收到客户端消息时的回调方法 OnClose标记此方法是断开websocke连接时的回调方法 OnError标记此方法是websocke发生异常时的回调方法 PathParam可以获取ServerEndpoint注解中绑定的路径模板参数 方法参数说明

1. onOpen方法参数 onOpen的可用参数在tomcat源码 org.apache.tomcat.websocket.pojo.PojoMethodMapping#getOnOpenArgs可以看到 public Object[] getOnOpenArgs(MapString,String pathParameters,Session session, EndpointConfig config) throws DecodeException {return buildArgs(onOpenParams, pathParameters, session, config, null,null);}因此可以看出OnOpen所标记方法的合法参数有 (1)PathParam标记的路径参数 (2)当前会话Session参数 (3)当前endpoint的配置详情EndpointConfig参数
2. onClose方法参数 onClose的可用参数在tomcat源码 org.apache.tomcat.websocket.pojo.PojoMethodMapping#getOnCloseArgs可以看到 public Object[] getOnCloseArgs(MapString,String pathParameters,Session session, CloseReason closeReason) throws DecodeException {return buildArgs(onCloseParams, pathParameters, session, null, null,closeReason);}因此可以看出OnClose所标记方法的合法参数有 (1)PathParam标记的路径参数 (2)当前会话Session参数 (3)当前连接关闭的原因CloseReason参数
3. onError方法参数 onError的可用参数在tomcat源码 org.apache.tomcat.websocket.pojo.PojoMethodMapping#getOnErrorArgs可以看到 public Object[] getOnErrorArgs(MapString,String pathParameters,Session session, Throwable throwable) throws DecodeException {return buildArgs(onErrorParams, pathParameters, session, null,throwable, null);}因此可以看出OnError所标记方法的合法参数有 (1)PathParam标记的路径参数 (2)当前会话Session参数 (3)发生异常的异常对象Throwable参数
4. onMessage方法参数 onMessage的可用参数在tomcat源码 org.apache.tomcat.websocket.pojo.PojoMethodMapping.MessageHandlerInfo#getMessageHandlers可以看到 public SetMessageHandler getMessageHandlers(Object pojo,MapString,String pathParameters, Session session,EndpointConfig config) {Object[] params new Object[m.getParameterTypes().length];for (Map.EntryInteger,PojoPathParam entry :indexPathParams.entrySet()) {PojoPathParam pathParam entry.getValue();String valueString pathParameters.get(pathParam.getName());Object value null;try {value Util.coerceToType(pathParam.getType(), valueString);} catch (Exception e) {DecodeException de new DecodeException(valueString,sm.getString(pojoMethodMapping.decodePathParamFail,valueString, pathParam.getType()), e);params new Object[] { de };break;}params[entry.getKey().intValue()] value;}SetMessageHandler results new HashSet(2);if (indexBoolean -1) {// Basicif (indexString ! -1 || indexPrimitive ! -1) {MessageHandler mh new PojoMessageHandlerWholeText(pojo, m,session, config, null, params, indexPayload, false,indexSession, maxMessageSize);results.add(mh);} else if (indexReader ! -1) {MessageHandler mh new PojoMessageHandlerWholeText(pojo, m,session, config, null, params, indexReader, true,indexSession, maxMessageSize);results.add(mh);} else if (indexByteArray ! -1) {MessageHandler mh new PojoMessageHandlerWholeBinary(pojo,m, session, config, null, params, indexByteArray,true, indexSession, false, maxMessageSize);results.add(mh);} else if (indexByteBuffer ! -1) {MessageHandler mh new PojoMessageHandlerWholeBinary(pojo,m, session, config, null, params, indexByteBuffer,false, indexSession, false, maxMessageSize);results.add(mh);} else if (indexInputStream ! -1) {MessageHandler mh new PojoMessageHandlerWholeBinary(pojo,m, session, config, null, params, indexInputStream,true, indexSession, true, maxMessageSize);results.add(mh);} else if (decoderMatch ! null decoderMatch.hasMatches()) {if (decoderMatch.getBinaryDecoders().size() 0) {MessageHandler mh new PojoMessageHandlerWholeBinary(pojo, m, session, config,decoderMatch.getBinaryDecoders(), params,indexPayload, true, indexSession, true,maxMessageSize);results.add(mh);}if (decoderMatch.getTextDecoders().size() 0) {MessageHandler mh new PojoMessageHandlerWholeText(pojo, m, session, config,decoderMatch.getTextDecoders(), params,indexPayload, true, indexSession, maxMessageSize);results.add(mh);}} else {MessageHandler mh new PojoMessageHandlerWholePong(pojo, m,session, params, indexPong, false, indexSession);results.add(mh);}} else {// ASyncif (indexString ! -1) {MessageHandler mh new PojoMessageHandlerPartialText(pojo,m, session, params, indexString, false,indexBoolean, indexSession, maxMessageSize);results.add(mh);} else if (indexByteArray ! -1) {MessageHandler mh new PojoMessageHandlerPartialBinary(pojo, m, session, params, indexByteArray, true,indexBoolean, indexSession, maxMessageSize);results.add(mh);} else {MessageHandler mh new PojoMessageHandlerPartialBinary(pojo, m, session, params, indexByteBuffer, false,indexBoolean, indexSession, maxMessageSize);results.add(mh);}}return results;}}因此可以看出OnMessage所标记方法的合法参数有 (1)PathParam标记的路径参数 (2)当前会话Session参数 (3)当数据是分块传输时表示当前消息时是否是最后一块数据的boolean Boolean参数 (4)字符输入流Reader参数 (5)二进制输入流InputStream参数 (6)原始的ByteBuffer参数 (7)字节数组byte[]参数 (8)字符串string参数 (9) Pong响应PongMessage参数 注意接收数据报文的参数4~5只能使用其中的一个否则可能导致IO异常IO流只能读取一次 ping和pong 上面的代码中我额外给websocket会话增加了一个PongMessage的处理方法onPong它的作用是接收客户端的pong回执消息。只有在服务端向客户端发送Ping请求时,服务端才能接收到Pong响应。这里的ping和pong就是类型于其他系统中的心跳机制用来检测客户端、服务端双方是否还在线如果超过了限定时间没有收到ping 和 pong消息服务端就会主动断开连接。 因此我在建立websocke连接的时候给当前回话设置了最大空闲时间(超过这个时间没有数据报文传输此连接就会自动断开)同时绑定了一个定时任务这个定时任务会定时发送ping消息来保活。 这里的onPong方法不是必须的没有它能保活onPong只是用来得到一个ping结果的通知。 3注册暴露端点 Configuration EnableWebSocket public class WebsocketConfig {Beanpublic ServerEndpointExporter serverEndpointExporter(){ServerEndpointExporter serverEndpointExporter new ServerEndpointExporter();//WebsocketHandler2如果是一个spring bean即有Component则不需要调用setAnnotatedEndpointClasses方法spring会自动探测有ServerEndpoint注解的bean//WebsocketHandler2如果只是一个包含ServerEndpoint注解的普通类(不是 spring bean),则需要在此调用setAnnotatedEndpointClasses方法手动注册Endpoint类型 // serverEndpointExporter.setAnnotatedEndpointClasses(WebsocketHandler2.class );return serverEndpointExporter;} } 配置类添加EnableWebSocket启用spring websocket功能. 另外还需配置一个Bean ServerEndpointExporter 如果Endpoint类是一个spring bean(即有Component)则不需要调用setAnnotatedEndpointClasses方法spring会自动探测含有ServerEndpoint注解的Bean如果Endpoint类只是一个包含ServerEndpoint注解的普通类(不是 spring bean),则需要在此调用setAnnotatedEndpointClasses方法手动注册Endpoint类型。 注意即使Endpoint类是spring bean ,WebsocketContainer也会再创建并使用这个类的一个新实例也就是说这个Endpoint中不能使用spring相关的功能典型的就是不能使用Autowire等注解自动注入Bean。其原因是websocket的默认端点配置org.apache.tomcat.websocket.server.DefaultServerEndpointConfigurator获取endpoint实例的逻辑是反射调用构造方法去创建一个新对象 public class DefaultServerEndpointConfiguratorextends ServerEndpointConfig.Configurator {Overridepublic T T getEndpointInstance(ClassT clazz)throws InstantiationException {try {return clazz.getConstructor().newInstance();} catch (InstantiationException e) {throw e;} catch (ReflectiveOperationException e) {InstantiationException ie new InstantiationException();ie.initCause(e);throw ie;}}当然你可以通过注入静态属性的方式来绕过这个限制。
   理论上说也可在ServerEndpoint注解的configurator属性指定为spring的org.springframework.web.socket.server.standard.SpringConfigurator也可以自动注入Bean依赖. ServerEndpoint(value /echo, configurator SpringConfigurator.class)public class EchoEndpoint {// …}SpringConfigurator它重写了获取Endpoint实例的方法逻辑getEndpointInstance它是直接到spring容器中去取这个bean,而不是创建一个新实例. 但实际在spring boot项目中上面的getEndpointInstance方法获取到的WebApplicationContext是null,也就没法从spring容器中获取这个Endpoint bean 基于spring WebSocketHandler实现websocket 了解WebSocketHandler 提前引入前面提到的websocket的starter 依赖 WebSocketHandler接口定义了5个方法 afterConnectionEstablished:建立连接后的回调方法 handleMessage:接收到客户端消息后的回调方法 handleTransportError: 数据传输异常时的回调方法 afterConnectionClosed: 连接关闭后的回调方法 supportsPartialMessages: 是否支持数据分块传输(最后一个分块传输,isLast是true) 它有两个主要的子类, 一个是处理纯文本数据的TextWebSocketHandler 另一个是处理二进制数据的BinaryWebSocketHandler。 我们实现websocket一般是继承这两个类并重写相应的方法。一般都需要重写afterConnectionEstablished handleTransportError handleTransportError afterConnectionClosed 这三个方法除此之外处理文本还要重写接收客户端消息后的回调方法handleTextMessage处理二进制数据需要重写接收客户端消息后的回调方法handleBinaryMessage。如果有需要得到ping结果回调还可以重写handlePongMessage方法 代码 Component public class WebsocketHandler1 extends TextWebSocketHandler {private final Logger log LoggerFactory.getLogger(getClass());private static final SetWebSocketSession sessions new ConcurrentSkipListSet(Comparator.comparing(WebSocketSession::getId));private static final ScheduledExecutorService scheduledExecutor Executors.newScheduledThreadPool(10);private static final MapString, ScheduledFuture? futures new ConcurrentHashMap();Overridepublic void afterConnectionEstablished(WebSocketSession session) throws Exception {SuppressWarnings(unchecked)AbstractWebSocketSessionSession standardSession (AbstractWebSocketSession) session;Session nativeSession standardSession.getNativeSession();nativeSession.setMaxIdleTimeout(1000*4);ScheduledFuture? future scheduledExecutor.scheduleWithFixedDelay(() - sendPing(session), 5, 5, TimeUnit.SECONDS);futures.put(session.getId(), future);log.info(open connect sessionId{}, session.getId());sessions.add(session);TextMessage msg new TextMessage(String.format(ws client(id%s) has connected, session.getId()));session.sendMessage(msg);}Overrideprotected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {log.info(receive client(id{}) msg{}, session.getId(), message.getPayload());TextMessage msg new TextMessage(String.format(reply your(id%s) msg%s, session.getId(), message.getPayload()));session.sendMessage(msg);}Overrideprotected void handlePongMessage(WebSocketSession session, PongMessage message) throws Exception {ByteBuffer payload message.getPayload();String s new String(payload.array());log.info(receive client(id{}) pong msg{}, session.getId(),s);}Overridepublic void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {log.error(client(id{}) error occur , session.getId(), exception);}Overridepublic void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {log.info(close ,status{}, status);sessions.remove(session);ScheduledFuture? future futures.get(session.getId());if (future ! null) {future.cancel(true);}}Overridepublic boolean supportsPartialMessages() {return true;}private void sendPing(WebSocketSession session) {if (session.isOpen()) {String replyContent String.format(Hello,client(id%s), session.getId());PingMessage msg new PingMessage(ByteBuffer.wrap(replyContent.getBytes(StandardCharsets.UTF_8)));try {session.sendMessage(msg);} catch (IOException e) {log.error(ping client(id{}) error, session.getId(), e);}}} } springboot内置的WebSocketHandler 前端html代码 !DOCTYPE html html langen headmeta charsetUTF-8meta nameviewport contentwidthdevice-width, initial-scale1.0titleWebSocket Chat/titlestylebody {font-family: Arial, sans-serif;}#chat-box {width: 100%;height: 300px;border: 1px solid #ccc;overflow-y: auto;padding: 10px;margin-bottom: 10px;background-color: #f9f9f9;white-space: pre-wrap;}#input-box {width: calc(50% - 90px);padding: 10px;margin-right: 10px;display: flex;justify-content: center}.btn {padding: 10px;}#btn-container {margin: 1px;display: flex;justify-content: center;gap: 5px;}#input-container {margin: 1px;display: flex;justify-content: center;gap: 5px;}/style /head bodydiv idchat-box/div div idinput-containerinput typetext idinput-box placeholderEnter your message/ /divdiv idbtn-containerbutton idconnect-button classbtnConnect/buttonbutton idclose-button classbtnClose/buttonbutton idclear-button classbtnClear/buttonbutton idsend-button classbtnSend/button /divscriptconst chatBox document.getElementById(chat-box);const inputBox document.getElementById(input-box);const sendButton document.getElementById(send-button);const connectBtn document.getElementById(connect-button);const closeBtn document.getElementById(close-button);const clearBtn document.getElementById(clear-button);let ws null;sendButton.addEventListener(click, () {if (ws null) {alert(no connect)return;}const message inputBox.value;if (message) {ws.send(message);chatBox.innerHTML You: message \n;chatBox.scrollTop chatBox.scrollHeight;inputBox.value ;}});clearBtn.addEventListener(click, () {chatBox.innerHTML ;});closeBtn.addEventListener(click, () {if (ws null) {alert(no connect)return;}console.log(prepare close ws);ws.close(1000, Normal closure);});connectBtn.addEventListener(click, () {if (ws ! null) {alert(already connected!)return;}let curWs new WebSocket(ws://localhost:7001/ws/Hews2df?id323colorred);curWs.onopen event {ws curWs;console.log(Connected to WebSocket server, event%s, JSON.stringify(event));};curWs.onmessage event {const message event.data;chatBox.innerHTML Server: message \n;chatBox.scrollTop chatBox.scrollHeight;};curWs.onclose event {ws null;console.log(Disconnected from WebSocket server, close code%s,close reason%s, event.code, event.reason);};curWs.onerror event {console.log(error occur, event%s, JSON.stringify(event))};});/script/body /html 演示效果