1、实时通信相关概念讲解
2、编写websocket启动类
3、编写websocket子处理器initalzer
4、编写chatHandler对于消息的处理
package com.imooc.netty.websocket;import java.time.LocalDateTime;import io.netty.channel.Channel;import io.netty.channel.ChannelHandlerContext;import io.netty.channel.SimpleChannelInboundHandler;import io.netty.channel.group.ChannelGroup;import io.netty.channel.group.DefaultChannelGroup;import io.netty.handler.codec.http.HttpObject;import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;import io.netty.util.concurrent.GlobalEventExecutor;/* * 处理消息的handler * TextWebSocketFrame：在netty中，是用于为websocket专门处理文本的对象，frame是消息的载体 */public class ChatHandler extends SimpleChannelInboundHandler<TextWebSocketFrame>{ ???//用于记录和管理所有客户端的channle ???private static ChannelGroup clients = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE); ???????@Override ???protected void channelRead0(ChannelHandlerContext ctx, TextWebSocketFrame msg) throws Exception { ???????//获取客户端传输过来的信息 ???????String content = msg.text(); ???????System.out.println("接收到的数据：" + content); ???????????????for(Channel channel : clients) { ???????????channel.writeAndFlush(new TextWebSocketFrame("[服务器在]" + LocalDateTime.now() ???????????????????+ "接收到消息，消息为：" + content)); ???????} ???????????????//与上面的for循环一致// ???????clients.writeAndFlush(new TextWebSocketFrame("[服务器在]" + LocalDateTime.now()// ???????????????????+ "接收到消息，消息为：" + content)); ???} ???/** ????* 当客户端连接服务端之后（打开连接） ????* 获取客户端的channle,并且放到ChannelGroup中去进行管理 ????*/ ???@Override ???public void handlerAdded(ChannelHandlerContext ctx) throws Exception { ???????clients.add(ctx.channel()); ???} ???@Override ???public void handlerRemoved(ChannelHandlerContext ctx) throws Exception { ???????//当触发handlerRemoved,ChannelGroup会自动移除客户端的channel ???????//clients.remove(ctx.channel()) ???????System.out.println("客户端断开，channel对应的长id为：" + ctx.channel().id().asLongText()); ???????System.out.println("客户端断开，channel对应的短id为：" + ctx.channel().id().asShortText()); ???}}5、前端websocket编写
<!DOCTYPE html><html> ???<head> ???????<meta charset="utf-8" /> ???????<title></title> ???</head> ???<body> ???????<div>发送消息：</div> ???????<input type="text" id="msgContent" /> ???????<input type="button" value="点我发送" onclick="CHAT.chat()" /> ???????????????<div>接受消息：</div> ???????<div id="receiveMsg" style="background-color: gainsboro;"></div> ???????????????<script type="application/javascript" > ???????????window.CHAT = { ???????????????socket: null, ???????????????init: function() { ???????????????????if (window.WebSocket) { ???????????????????????CHAT.socket = new WebSocket("ws://7dxppj.natappfree.cc/ws"); ???????????????????????CHAT.socket.onopen = function() { ???????????????????????????console.log("连接建立成功..."); ???????????????????????}, ???????????????????????CHAT.socket.onclose = function() { ???????????????????????????console.log("连接关闭..."); ???????????????????????}, ???????????????????????CHAT.socket.onerror = function() { ???????????????????????????console.log("发生错误..."); ???????????????????????}, ???????????????????????CHAT.socket.onmessage = function(e) { ???????????????????????????console.log("接收到消息" + e.data); ???????????????????????????var receiveMsg = document.getElementById("receiveMsg"); ???????????????????????????var html = receiveMsg.innerHTML; ???????????????????????????receiveMsg.innerHTML = html + "</br>" + e.data; ???????????????????????} ???????????????????????????????????????????} else { ???????????????????????alert("浏览器不支持websocket协议..."); ???????????????????} ???????????????}, ???????????????chat: function() { ???????????????????var msg = document.getElementById("msgContent"); ???????????????????CHAT.socket.send(msg.value); ???????????????} ???????????}; ???????????????????????CHAT.init(); ???????</script> ???</body></html>使用netty构建websocket服务器
原文地址：https://www.cnblogs.com/bozzzhdz/p/9998315.html