springboot 項目==基於websocket的服務端推送消息。

1.建立springboot項目，首先咱們仍是先引入依賴

<!-- webSocket  begin-->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
<!-- webSocket  end-->

2.建立配置類   WebSocketH5Config

@Configuration
@EnableWebSocket
public class WebSocketH5Config implements WebSocketConfigurer {
    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
   //handler是webSocket的核心，配置入口
   registry.addHandler(new MyHandler(), "/myHandler/{ID}").setAllowedOrigins("*").addInterceptors(new WebSocketInterceptor());
    }

3.建立服務類   MyHandler

@Service
public class MyHandler implements WebSocketHandler {

    //在線用戶列表
    private static final Map<String, WebSocketSession> users;

    static {
        users = new HashMap<>();
    }

    //新增socket
    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        String ID = session.getUri().toString().split("ID=")[1];
        //使用URLDecoder進行解碼，由於前段傳來的就是亂碼
        String decode = URLDecoder.decode(ID, "UTF-8");
        System.out.println("成功創建鏈接,註冊帳號爲" + decode);
        if (decode != null) {
            users.put(decode, session);
            session.sendMessage(new TextMessage("成功創建socket鏈接"));
            System.out.println(session);
        }
        System.out.println("當前在線人數：" + users.size());
    }

    //接收socket信息(接受客戶端的信息)
    @Override
    public void handleMessage(WebSocketSession webSocketSession, WebSocketMessage<?> webSocketMessage) throws Exception {
        try {
            JSONObject jsonobject = JSONObject.fromObject(webSocketMessage.getPayload());
//            System.out.println(jsonobject.get("id"));
//            System.out.println(jsonobject.get("message") + ":來自" + (String) webSocketSession.getAttributes().get("WEBSOCKET_USERID") + "的消息");
            Map map = new HashMap(2);
            map.put("id", jsonobject.get("id"));
            map.put("message", jsonobject.get("message").toString());
            String msg = JSON.toJSONString(map);
            //將消息發送到mq
            Sender been = (Sender) AppContext.getBeen(Sender.class);
            been.send(msg);
            sendMessageToUser(jsonobject.get("id") + "", new TextMessage(msg));
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    /**
     * 發送信息給指定用戶 （服務端給指定用戶發送消息）
     *
     * @param clientId
     * @param message
     * @return
     */
    public boolean sendMessageToUser(String clientId, TextMessage message) {
        if (users.get(clientId) == null) return false;
        WebSocketSession session = users.get(clientId);
//        System.out.println("sendMessage:" + session);
        if (!session.isOpen()) return false;
        try {
            session.sendMessage(message);
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
        return true;
    }

    /**
     * 廣播信息（服務端給全部用戶推送消息）
     *
     * @param message
     * @return
     */
    public boolean sendMessageToAllUsers(TextMessage message) {
        boolean allSendSuccess = true;
        Set<String> clientIds = users.keySet();
        WebSocketSession session = null;
        for (String clientId : clientIds) {
            try {
                session = users.get(clientId);
                if (session.isOpen()) {
                    session.sendMessage(message);
                }
            } catch (IOException e) {
                e.printStackTrace();
                allSendSuccess = false;
            }
        }

        return allSendSuccess;
    }


    @Override
    public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
        if (session.isOpen()) {
            session.close();
        }
        System.out.println("鏈接出錯");
        users.remove(getClientId(session));
    }

    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
        System.out.println("鏈接已關閉：" + status);
        users.remove(getClientId(session));
    }

    @Override
    public boolean supportsPartialMessages() {
        return false;
    }

    /**
     * 獲取用戶標識
     *
     * @param session
     * @return
     */
    private Integer getClientId(WebSocketSession session) {
        try {
            Integer clientId = (Integer) session.getAttributes().get("WEBSOCKET_USERID");
            return clientId;
        } catch (Exception e) {
            return null;
        }
    }

    public Map<String, WebSocketSession> getAllUsers() {
        return users;
    }
}

4.建立配置類   WebSocketInterceptor

 

public class WebSocketInterceptor implements HandshakeInterceptor {

    //在握手以前執行該方法, 繼續握手返回true, 中斷握手返回false. 經過attributes參數設置WebSocketSession的屬性
    @Override
    public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse serverHttpResponse, WebSocketHandler webSocketHandler, Map<String, Object> attributes) throws Exception {
        if (request instanceof ServletServerHttpRequest) {
            String ID = request.getURI().toString().split("ID=")[1];
            //使用URLDecoder進行解碼，由於前段傳來的就是亂碼
            String decode = URLDecoder.decode(ID, "UTF-8");
            System.out.println("當前session的ID=" + decode);
            //ServletServerHttpRequest serverHttpRequest = (ServletServerHttpRequest) request;
            //HttpSession session = serverHttpRequest.getServletRequest().getSession();
            attributes.put("WEBSOCKET_USERID", decode);
        }
        return true;
    }

    //完成握手以後執行該方法
    @Override
    public void afterHandshake(ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse, WebSocketHandler webSocketHandler, Exception e) {
        System.out.println("進來webSocket的afterHandshake攔截器！");
    }
}

5.jsp頁面

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %><!DOCTYPE html><html><head>    <title>socket.html</title>    <meta name="keywords" content="keyword1,keyword2,keyword3">    <meta name="description" content="this is my page">    <%--<meta name="content-type" content="text/html" charset="UTF-8">--%>    <%--<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">--%>    <!--<link rel="stylesheet" type="text/css" href="./styles.css">--></head><body>Welcome<br/><input id='ipt' type='text' name="註冊"/><button onclick="getVal()">註冊</button><br><input id="text" type="text"/><button onclick="">發送的內容</button><br><input id='ipts' type='text' name="發給誰"/><button onclick="send()">發給誰</button><button onclick="closeWebSocket()">斷開鏈接</button></div><!-- 公共JS --> <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script><script type="text/javascript" src="../webSocket/jquery.min.js"></script><script type="text/javascript">    var websocket = null;    function getVal() {        //建立WebSocket        connectWebSocket();    }    //強制關閉瀏覽器  調用websocket.close（）,進行正常關閉    window.onunload = function () {        //關閉鏈接        closeWebSocket();    }    //創建WebSocket鏈接    function connectWebSocket() {        var user = document.getElementById('ipt');//找到id是ipt的input節點;        var userID = user.value;        // alert(userID);        console.log("開始...");        //創建webSocket鏈接        websocket = new WebSocket("ws://192.168.1.46:9999/myHandler/ID=" + userID);        // websocket = new WebSocket("ws://94.191.34.57:9999/myHandler/ID=" + userID);        //打開webSokcet鏈接時，回調該函數        websocket.onopen = function () {            console.log("onpen");        }        //關閉webSocket鏈接時，回調該函數        websocket.onclose = function () {            //關閉鏈接            console.log("onclose");        }        //接收信息        websocket.onmessage = function (msg) {            console.log("receive msg");            console.log(msg.data);            alert(msg.data)        }    }    //發送消息    function send() {        var user = document.getElementById('ipts');//找到id是ipt的input節點;        var userID = user.value;        // alert(userID);        var postValue = {};        postValue.id = userID;        postValue.message = $("#text").val();        websocket.send(JSON.stringify(postValue));    }    //關閉鏈接    function closeWebSocket() {        if (websocket != null) {            websocket.close();        }    }</script><script type="text/javascript" charset="UTF-8"></script></body></html>