Java Implementation WebSocket Ultimate guide

1. Add Dependency in Pom

<dependency>            <groupId>org.springframework</groupId>            <artifactId> spring-websocket</artifactid>            <version>${spring-version}</version>        </dependency >                <dependency>            <groupId>org.springframework</groupId>            <artifactId> spring-messaging</artifactid>            <version>${spring-version}</version>        </dependency >

2. Add WebSocket interception in Spring-mvc.xml

<websocket:handlers allowed-origins= "*" >        <websocket:mapping path= "/ws" handler= "MyHandler"/>        <websocket:handshake-interceptors>            <bean class= "Com.cloudunicomm.interceptor.HandshakeInterceptor" />        </websocket:handshake-interceptors>    </websocket:handlers>    <bean id= "MyHandler" class= "Com.cloudunicomm.interceptor.MySocketHandler"/>

3. Add Mysockethandler Class

Package Com.cloudunicomm.interceptor;import Java.io.ioexception;import Java.util.hashmap;import java.util.Iterator ; Import Java.util.map;import Java.util.map.entry;import Java.util.set;import Java.util.concurrent.copyonwritearrayset;import Org.slf4j.logger;import Org.slf4j.loggerfactory;import Org.springframework.beans.factory.annotation.autowired;import Org.springframework.data.redis.core.listoperations;import org.springframework.data.redis.core.RedisTemplate; Import Org.springframework.web.socket.closestatus;import Org.springframework.web.socket.textmessage;import Org.springframework.web.socket.websocketmessage;import Org.springframework.web.socket.websocketsession;import Org.springframework.web.socket.handler.textwebsockethandler;import Com.alibaba.fastjson.jsonobject;import   Com.cloudunicomm.vo.User; public class Mysockethandler extends Textwebsockethandler {private static final Logger Logger = Loggerfactory.getlogg    ER (mysockethandler.class); Number of people on line private static int COunt;     private static copyonwritearrayset<websocketsession> set = new copyonwritearrayset<> ();    public static map<string,websocketsession> SessionID = new hashmap<string,websocketsession> ();          Private Websocketsession session;            @Autowiredprivate redistemplate<string,string> redistemplate; @Override public void Afterconnectionestablished (websocketsession session) {map<string, object> Map = ses    Sion.getattributes ();    String UserID = map.get ("userid"). toString ();       Sessionid.put (userid, session);         This.session = session;         try{Set.add (this.session);         }catch (Exception e) {e.printstacktrace ();         } mysockethandler.addonlinecount ();      System.out.println ("Current number of connections:" + getonlinecount ()); } public void afterconnectionclosed (websocketsession session,closestatus closestatus) {this.session = Sessio       N String UserID = session.getattributes (). Get ("userid"). toString ();       Redistemplate.delete ("Seat_" +userid);       Session.getattributes (). Remove ("userid");         Set.remove (this.session);         Subonlinecount ();      System.out.println ("Current number of connections:" + getonlinecount ()); } public void Handlemessage (Websocketsession session,websocketmessage<?>message) {System.out.print        ln ("From client message:" +message.getpayload () + "_" + Session.getid ());            Send to everyone/* for (websocketsession Ssion:set) {try {ssion.sendmessage (message);             }catch (IOException e) {e.printstacktrace ();           }} *//Parse message Modify User state try{//id:state,//username:sip:[email protected]:9060       string[] state = Message.getpayload (). toString (). Split ("_");       listoperations<string,string> value = Redistemplate.opsforlist ();       String val = value.rightpop ("Seat_" +state[0]). toString (); User user = (user) Jsonobject.tojaVaobject (Jsonobject.parseobject (Val), User.class);       User.setstate (Integer.parseint (state[1));       The actual is to parse out now first write dead User.setnext_hop ("123.57.144.26:9060/udp");       User.setto ("<sip:[email protected]:9060>");       String struser = jsonobject.tojsonstring (user);       Value.leftpush ("Seat_" +user.getid (). toString (), struser);       }catch (Exception e) {logger.error (E.getmessage (), E);      }} public static int Getonlinecount () {return count;      } public static void Addonlinecount () {count++;      } public static void Subonlinecount () {count--;  /** * Give the specified connection push message * @param session * @param message * */public string pushmsg (string SessionID, String message) {for (websocketsession Ssion:set) {try {if (Sessionid.equals (ssion                    . GetId ())) {Ssion.sendmessage (new TextMessage (message)); Return "machine:" + SEssionid+ "Push Success";             }}catch (IOException e) {e.printstacktrace ();      }} Return "Push failed";          /** * to all connections * @param message * @return */public string pushmsg (String message) {          int i = 0;                 for (Websocketsession Ssion:set) {try {ssion.sendmessage (new TextMessage (message));             i++;             }catch (IOException e) {e.printstacktrace ();         }} return "Total" + i + "get Push";   }}

4. Add Handshakeinterceptor Class

　

Package Com.cloudunicomm.interceptor;import Java.util.map;import Javax.servlet.http.httpsession;import Org.springframework.http.server.serverhttprequest;import Org.springframework.http.server.ServerHttpResponse; Import Org.springframework.http.server.servletserverhttprequest;import Org.springframework.web.socket.websockethandler;import   Org.springframework.web.socket.server.support.HttpSessionHandshakeInterceptor; public class Handshakeinterceptor extends Httpsessionhandshakeinterceptor {/* * handshake pre-processing action */@Overrid             E public boolean beforehandshake (ServerHTTPRequest request, serverhttpresponse response, Websockethandler handler,               Map<string,object> map) throws Exception {System.out.println ("front handshake"); if (Request instanceof Servletserverhttprequest) {servletserverhttprequest ServletRequest = (servletserverhttprequest           ) Request;          HttpSession HttpSession = Servletrequest.getservletrequest (). GetSession (True);if (null! = httpSession) {//String UserID = Httpsession.getattribute ("userid"). toString ();             String UserID = Httpsession.getattribute ("userid"). toString ();          Map.put ("userid", UserID);      }} return Super.beforehandshake (request, response, handler, map); } @Override public void Afterhandshake (ServerHTTPRequest request,serverhttpresponse Response,websockethandl      ER wshandler,exception ex) {Super.afterhandshake (Request, Response, Wshandler, ex);   }   }

5, add TestController

Package Com.cloudunicomm.controller;import Javax.servlet.http.httpservletrequest;import Javax.servlet.http.httpservletresponse;import Org.springframework.stereotype.controller;import Org.springframework.web.bind.annotation.RequestMapping, @Controller @RequestMapping ("/im") public class      TestController {/* @Bean public mysorkethandle Mysorkethandle () {return new Mysorkethandle ();            } */@RequestMapping ("/page") public String page (httpservletrequest request, httpservletresponse response) {      return "Impage"; }/* @ResponseBody @RequestMapping ("/push") public string push (@RequestParam (required = false) string SE         Ssionid, httpservletresponse response) {String msg= "";             if (Stringutils.isempty (sessionId)) {msg =mysorkethandle (). PUSHMSG ("Server pushes information out");         SYSTEM.OUT.PRINTLN (msg);             }else{msg =mysorkethandle (). Pushmsg (sessionId, "server pushes information out"); System.out.priNTLN (msg);      } return msg;  }  */}

6. Add JSP

<%@ page language= "java" contenttype= "text/html; Charset=utf-8 "pageencoding=" Utf-8 "%><! DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" "Http://www.w3.org/TR/html4/loose.dtd" >
 7. Login Controller 
 
Package Com.cloudunicomm.controller;import Java.util.list;import Javax.servlet.http.httpservletrequest;import Javax.servlet.http.httpservletresponse;import Org.apache.commons.lang.stringutils;import Org.springframework.beans.factory.annotation.autowired;import Org.springframework.data.redis.core.listoperations;import org.springframework.data.redis.core.RedisTemplate; Import Org.springframework.stereotype.controller;import Org.springframework.web.bind.annotation.CrossOrigin; Import Org.springframework.web.bind.annotation.requestmapping;import Org.springframework.web.bind.annotation.requestparam;import Org.springframework.web.bind.annotation.responsebody;import Com.alibaba.fastjson.jsonobject;import Com.cloudunicomm.service.userservice;import Com.cloudunicomm.utils.resultmessage;import Com.cloudunicomm.vo.User ; @Controllerpublic class Logincontroller {@Autowiredprivate userservice userservice; @Autowiredprivate redistemplate <String,String> redistemplate; @CrossOrigin (Origins = "*", MAXAGE = +) @RequestMapping ("login") @ResponseBodypublic resultmessage Login (httpservletrequest request, HttpServletResponse response, @RequestParam (name= "username", Required=false) String username, @RequestParam (name= " Password ", required=false) String password) {if (Stringutils.isempty (username) | | Stringutils.isempty (password)) {return Resultmessage.getfail (). Setmessage ("Username password cannot be empty! ");} User user = Userservice.authusernmaandpassword (username,password), if (user = = null) {return Resultmessage.getfail (). Setmessage ("User name password is wrong! ");} String str = redistemplate.opsforlist (). Rightpopandleftpush ("Seat_" +user.getid (), "Seat_" +user.getid ()); if (null! = STR) {return resultmessage.getfail (). Setmessage ("Do not re-login! ");} Login successfully added user to Redis IsLogin modified to online state modified to free user.setislogin (0); user.setstate (0); listoperations<string,string> redislist = Redistemplate.opsforlist (); String struser = jsonobject.tojsonstring (user),//left-to-right deposit stack Redislist.leftpush ("Seat_" +user.getid (). toString (), struser); Request.getsession (). SetAttribute ("UserID ", User.getid ()); return resultmessage.getsuccess (). SetData (User.getid ());}} 
　　
　
8. Precautions
1) If the interceptor is to be commented out in the project or the WebSocket link fails
2) If the test is a remote call, the address must be the same
Java Implementation WebSocket Ultimate guide