WebSocket implements a simple web chat room __web

1. Requires Tomcat7.0 so server 2. JDK7.0 3. Manually add the Tomcat7.0 in the Lib directory of three packets Catalina.jar, Tomcat-coyote.jar, Websocket-api.jar 4. After the project is deployed, delete the Catalina.jar, Tomcat-coyote.jar, Websocket-api.jar three packages under the current project in the server. 5. The project directory structure is as follows



Servlet code
Package com.yc.websockets;
Import java.io.IOException; Import Java.nio.ByteBuffer; Import Java.nio.CharBuffer; Import java.util.ArrayList; Import java.util.List;
Import Javax.servlet.http.HttpServletRequest; Import javax.servlet.http.HttpSession; Import Javax.websocket.OnClose; Import Javax.websocket.OnMessage; Import Javax.websocket.OnOpen; Import javax.websocket.Session; Import Javax.websocket.server.ServerEndpoint;
Import Org.apache.catalina.websocket.MessageInbound; Import Org.apache.catalina.websocket.StreamInbound; Import Org.apache.catalina.websocket.WebSocketServlet; Import Org.apache.catalina.websocket.WsOutbound;
@SuppressWarnings ({"Deprecation", "unused", "serial"}) public class Websockettest extends Websocketservlet {private static list<mymessageinbound> userlist = new arraylist<mymessageinbound> (); Private HttpSession session;
@Override protected Streaminbound createwebsocketinbound (String str, httpservletrequest request) {Session=reques         T.getsession ();     return new Mymessageinbound (); }
Private class Mymessageinbound extends Messageinbound {wsoutbound myoutbound;
/** * When the user logs in, the WebSocket handshake is complete, created, Wsoutbound used to send data to the client */public void OnOpen (Wsoutbound outbound) {                 try {System.out.println ("Open Client.");                 This.myoutbound = outbound; Userlist.add (this); Add current user//Send message to Client Outbound.writetextmessage (Charbuffer.wrap ("hello!"))             ;             } catch (IOException e) {e.printstacktrace (); }         }
/** * When the user exits, the WebSocket shutdown event, the parameter status should come from a few constants defined in Org.apache.catalina.websocket.Constants *, you can refer to the documentation or check the tomcat source */ @Override public void OnClose (Int. status) {Userlist.remove (this);//Remove Current user}
/** * Accept the message sent by the user, there is text message data arrives */@Override public void Ontextmessage (Charbuffer cb) throws IO Exception {for (Mymessageinbound mmib:userlist) {//loop sends the current user's information to all online users charbuffer buffer = Cha                 Rbuffer.wrap (CB); Mmib.myoutbound.writeTextMessage (buffer); Invokes the sending method of the specified user to send the current user information mmib.myoutbound.flush (); Empty Cache}}
/** * has binary message data arrives, temporarily did not study this function under what circumstances trigger, JS WebSocket supposedly should only send text information only to * * @Override public Voi d onbinarymessage (Bytebuffer bb) throws IOException {}}}

Web. XML configuration file
<?xml version= "1.0" encoding= "UTF-8"?> <web-app version= "3.0" xmlns= "Http://java.sun.com/xml/ns/javaee" Xmlns:xsi= "Http://www.w3.org/2001/XMLSchema-instance" xsi:schemalocation= "HTTP://JAVA.SUN.COM/XML/NS/JAVAEE; Http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd "> <display-name></display-name> <servlet> <servlet-name>webServlet</servlet-name> <servlet-class>com.yc.websockets.websockettest</ servlet-class> </servlet> <servlet-mapping> <servlet-name>webServlet</servlet-name> <url-pattern>/webServlet</url-pattern> </servlet-mapping> <welcome-file-list> < Welcome-file>index.html</welcome-file> </welcome-file-list> </web-app>
Index.html
<! DOCTYPE html> WebSocket handshake Complete, connection successful callback//There is a question, supposedly new websocket will start to connect, if the connection before the setting OnOpen successful, will also trigger this callback Ws.onopen = function () {// Request succeeded};
Receives a text message sent by the server, Event.data represents the text content ws.onmessage = function (message) {document.getElementById ("Talkinfo"). innerhtml+= message.data+ "Turn off WebSocket Callback ws.onclose = function () {//alert (' closed! ');};
By websocket you want to send a text message to the server function Posttoserver () {Ws.send (document.getElementById ("content"). Value); document.getElementById ("Content"). Value = "";}
Close WebSocket function Closeconnect () {ws.close ();} </script> <style> * {margin:0 auto; padding:0px; font -size:12px; Font-family: "Microsoft Jas Black"; line-height:26px; }
#bigbox {margin:0px auto; padding:0px; width:70%;}
#talkInfo {width:100%; height:500px; border:1px solid red; overflow:scorll;}
#operation {width:100%; height:30px; margin-top:10px;}
#content {height:30px; line-height:30px;} </style>