1. 前端
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>WebSocket Chat</title>
</head>
<body><script type="text/javascript">var socket;if (!window.WebSocket) {window.WebSocket = window.MozWebSocket;}if (window.WebSocket) {socket = new WebSocket("ws://localhost:8088/ws");socket.onmessage = function(event) {console.log("receive message:" + event.data)var ele = document.getElementById('respText');ele.value = ele.value + "\n" + event.data;};socket.onopen = function(event) {var ele = document.getElementById('respText');ele.value = "连接开启";}socket.onclose = function(event) {var ele = document.getElementById('respText');ele.value = ele.value + "连接被关闭";}} else {alert("Your browser does not support WebSocket!");}function sendMessage(message) {if (!window.WebSocket) {alert("Your browser does not support WebSocket!")return;}if (socket.readyState == WebSocket.OPEN) {socket.send(message);console.log("send message:" + message)} else {alert("The connection is not open.");}}</script><form onsubmit="return false"><h3>WebSocket Chat</h3><textarea name="" id= "respText" style="width: 500px;height: 300px"></textarea><input type="text" name="message" style="width: 300px" value="Welcome to chat.marding.cn"><input type="button" value="发送" onclick="sendMessage(this.form.message.value)"></input>
</form>
</body>
</html>
2. 后端
@Component
public class WebSocketChatServer {private int port;public WebSocketChatServer(@Value("${websocket.port:8088}") int port) {this.port = port;}@PostConstructpublic void init() {try {this.run();} catch (Exception e) {throw new RuntimeException(e);}}public static void main(String[] args) throws Exception {}public void run() throws Exception {NioEventLoopGroup bossGroup = new NioEventLoopGroup(1);NioEventLoopGroup workerGroup = new NioEventLoopGroup();try {ServerBootstrap serverBootstrap = new ServerBootstrap();serverBootstrap.group(bossGroup,workerGroup).channel(NioServerSocketChannel.class).childHandler(new WebSocketChatServerInitializer()).option(ChannelOption.SO_BACKLOG,128).childOption(ChannelOption.SO_KEEPALIVE,true);ChannelFuture channelFuture = serverBootstrap.bind(port).sync();System.out.println("bind port success");channelFuture.channel().closeFuture().sync();} finally {workerGroup.shutdownGracefully();bossGroup.shutdownGracefully();System.out.println("server stop");}}}
public class WebSocketChatServerInitializer extends ChannelInitializer<SocketChannel> {@Overrideprotected void initChannel(SocketChannel ch) throws Exception {ch.pipeline().addLast(new HttpServerCodec()).addLast(new HttpObjectAggregator(64 * 1024)).addLast(new ChunkedWriteHandler()).addLast(new HttpRequestHandler("/ws")).addLast(new WebSocketServerProtocolHandler("/ws")).addLast(new TextWebSocketFrameHandler());}
}
public class TextWebSocketFrameHandler extends SimpleChannelInboundHandler<TextWebSocketFrame> {public static ChannelGroup channels = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE);@Overridepublic void handlerAdded(ChannelHandlerContext ctx) throws Exception {Channel channel = ctx.channel();channels.add(channel);channels.writeAndFlush(new TextWebSocketFrame(channel.remoteAddress() + "加入"));System.out.println(channel.remoteAddress() + "加入");}@Overridepublic void handlerRemoved(ChannelHandlerContext ctx) throws Exception {Channel channel = ctx.channel();channels.writeAndFlush(new TextWebSocketFrame(channel.remoteAddress() + "离开"));System.out.println(channel.remoteAddress() + "离开");}@Overridepublic void channelActive(ChannelHandlerContext ctx) throws Exception {Channel channel = ctx.channel();System.out.println(channel.remoteAddress() + "在线");}@Overridepublic void channelInactive(ChannelHandlerContext ctx) throws Exception {Channel channel = ctx.channel();System.out.println(channel.remoteAddress() + "掉线");}@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {Channel channel = ctx.channel();System.out.println(channel.remoteAddress() + " 异常");cause.printStackTrace();ctx.close();}@Overrideprotected void channelRead0(ChannelHandlerContext ctx, TextWebSocketFrame msg) throws Exception {String text = msg.text();System.out.println("收到消息：" + text);Channel channel = ctx.channel();text = WordsFilter.filter(text);for (Channel ch : channels){if (channel != ch){ch.writeAndFlush(new TextWebSocketFrame(channel.remoteAddress() + ":" + text));}else {ch.writeAndFlush(new TextWebSocketFrame("[you]" + text));}}}}
public class HttpRequestHandler extends SimpleChannelInboundHandler<FullHttpRequest> {private final String wsUri;private static final File PAGE_FILE;static {URL location = HttpRequestHandler.class.getProtectionDomain().getCodeSource().getLocation();String path = null;try {path = location.toURI() + "wsChatClient.html";path = path.contains("file:") ? path.substring(5):path;PAGE_FILE = new File("\"C:\\Jlearning\\wsChatClient.html\"");} catch (URISyntaxException e) {throw new RuntimeException(e);}}public HttpRequestHandler(String wsUri) {this.wsUri = wsUri;}@Overrideprotected void channelRead0(ChannelHandlerContext ctx, FullHttpRequest request) throws Exception {if (wsUri.equalsIgnoreCase(request.uri())) {ctx.fireChannelRead(request.retain());return;}if (HttpUtil.is100ContinueExpected(request)) {send100Continue(ctx);}byte[] fileContent;try (RandomAccessFile file = new RandomAccessFile(PAGE_FILE, "r")) {fileContent = new byte[(int) file.length()];file.readFully(fileContent);} catch (IOException e) {DefaultFullHttpResponse errorResponse = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.INTERNAL_SERVER_ERROR);ctx.writeAndFlush(errorResponse);return;}DefaultFullHttpResponse resp = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK);resp.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/html; charset=UTF-8");boolean keepAlive = HttpUtil.isKeepAlive(request);if (keepAlive) {resp.headers().set(HttpHeaderNames.CONTENT_LENGTH, fileContent.length);resp.headers().set(HttpHeaderNames.CONNECTION, HttpHeaderValues.KEEP_ALIVE);}resp.content().writeBytes(fileContent);ChannelFuture channelFuture = ctx.writeAndFlush(resp);if (!keepAlive) {channelFuture.addListener(ChannelFutureListener.CLOSE);}channelFuture.addListener(new ChannelFutureListener() {@Overridepublic void operationComplete(ChannelFuture channelFuture) throws Exception {System.out.println("response empty last content success !");}});}private void send100Continue(ChannelHandlerContext ctx) {DefaultFullHttpResponse resp = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.CONTINUE);ctx.writeAndFlush(resp);}@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {Channel channel = ctx.channel();System.out.println("client " + channel.remoteAddress() + "异常");cause.printStackTrace();ctx.close();}
}
public class WordsFilter {public static Map<String, Object> dictionaryMap = new HashMap<>();public static void initMap(Collection<String> words) {if (words == null) {System.out.println("敏感词列表不能为空");return ;}Map<String, Object> map = new HashMap<>(words.size());Map<String, Object> curMap = null;Iterator<String> iterator = words.iterator();while (iterator.hasNext()) {String word = iterator.next();curMap = map;int len = word.length();for (int i =0; i < len; i++) {String key = String.valueOf(word.charAt(i));Map<String, Object> wordMap = (Map<String, Object>) curMap.get(key);if (wordMap == null) {wordMap = new HashMap<>(2);wordMap.put("isEnd", "0");curMap.put(key, wordMap);}curMap = wordMap;if (i == len -1) {curMap.put("isEnd", "1");}}}dictionaryMap = map;}static {List<String> list = new ArrayList<>();list.add("坏蛋");list.add("笨蛋");initMap(list);}private static int checkWord(String text, int beginIndex) {if (dictionaryMap == null) {throw new RuntimeException("字典不能为空");}boolean isEnd = false;int wordLength = 0;Map<String, Object> curMap = dictionaryMap;int len = text.length();for (int i = beginIndex; i < len; i++) {String key = String.valueOf(text.charAt(i));curMap = (Map<String, Object>) curMap.get(key);if (curMap == null) {break;} else {wordLength ++;if ("1".equals(curMap.get("isEnd"))) {isEnd = true;}}}if (!isEnd) {wordLength = 0;}return wordLength;}public static String filter(String text) {StringBuilder result = new StringBuilder();int length = text.length();int position = 0;while (position < length) {int matchLength = checkWord(text, position);if (matchLength > 0) {result.append("**");position += matchLength;} else {result.append(text.charAt(position));position++;}}return result.toString();}public static Map<String, Integer> matchWords(String text) {Map<String, Integer> wordMap = new HashMap<>();int len = text.length();for (int i = 0; i < len; i++) {int wordLength = checkWord(text, i);if (wordLength > 0) {String word = text.substring(i, i + wordLength);if (wordMap.containsKey(word)) {wordMap.put(word, wordMap.get(word) + 1);} else {wordMap.put(word, 1);}i += wordLength - 1;}}return wordMap;}
}
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