1. 專案介紹
- 客戶端頁面index.html可以輸入訊息，點選傳送，通過ws協議傳送到伺服器端；
- 伺服器端收到客戶端訊息後，廣播給各個客戶端；
- 伺服器端頁面server.html，可以輸入訊息，點選傳送，通過ws雙工通訊推送給客戶端；
- 客戶端有顯示伺服器端廣播訊息的區域。
2. 專案目錄結構
3. 專案程式碼分析
3.1 pom.xml檔案新增必要依賴
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!--WebSocket-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>bootstrap</artifactId>
<version>3.3.7-1</version>
</dependency>
</dependencies>
3.2 .java程式碼
- 新建WebSocket 的配置類WebSocketConfig.java
package com.springboot.websocket.websocket.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;
/**
* WebSocket配置類
*
*/
@Configuration
public class WebSocketConfig {
@Bean
public ServerEndpointExporter serverEndpointExporter() {
return new ServerEndpointExporter();
}
}
package com.springboot.websocket.websocket.config;
import org.springframework.stereotype.Component;
import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;
/**
* WebSocket的服務端
* 因為WebSocket是類似客戶端服務端的形式(採用ws協議)，
* 那麼這裡的WebSocketServer其實就相當於一個ws協議的Controller
* 直接@ServerEndpoint(“/websocket”)@Component啟用即可，
* 然後在裡面實現@OnOpen,@onClose,@onMessage等方法
*/
@ServerEndpoint("/websocket")
@Component
public class WebSocketServer {
//靜態變數，用來記錄當前線上連線數。應該把它設計成執行緒安全的。可選的
private static int onlineCount = 0;
//concurrent包的執行緒安全Set，用來存放每個客戶端對應的MyWebSocket物件。必須要有的
private static CopyOnWriteArraySet<WebSocketServer>
webSocketSet = new CopyOnWriteArraySet<WebSocketServer>();
//與某個客戶端的連線會話，需要通過它來給客戶端傳送資料，必須
private Session session;
/**
* 連線建立成功呼叫的方法
*/
@OnOpen
public void onOpen(Session session) {
this.session = session;
webSocketSet.add(this); //加入set中
addOnlineCount(); //線上數加1
//一旦連線成功後就在控制檯列印資訊
System.out.println("有新視窗開始監聽,當前線上人數為" + getOnlineCount());
try {
//往客戶端傳送訊息
sendMessage("連線成功");
} catch (IOException e) {
System.out.println("WebSocket IO異常");
}
}
/**
* 連線關閉呼叫的方法
*/
@OnClose
public void onClose() {
webSocketSet.remove(this); //從set中刪除
subOnlineCount(); //線上數減1
System.out.println("有連線關閉！當前線上人數為" + getOnlineCount());
}
/**
* 收到客戶端訊息後呼叫的方法
*
* @param message 客戶端傳送過來的訊息
*/
@OnMessage
public void onMessage(String message, Session session) {
//message 是從客戶端傳送過來的訊息，並在控制檯列印
System.out.println("收到客戶端的資訊:" + message);
//群發訊息
for (WebSocketServer item : webSocketSet) {
try {
item.sendMessage(message);
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* @param session
* @param error
*/
@OnError
public void onError(Session session, Throwable error) {
System.out.println("發生錯誤");
error.printStackTrace();
}
/**
* 實現伺服器主動推送
*/
public void sendMessage(String message) throws IOException {
this.session.getBasicRemote().sendText(message);
}
/**
* 群發自定義訊息
*/
public static void sendInfo(String message) throws IOException {
System.out.println("推送訊息內容:" + message);
for (WebSocketServer item : webSocketSet) {
try {
item.sendMessage(message);
} catch (IOException e) {
continue;
}
}
}
public static synchronized int getOnlineCount() {
return onlineCount;
}
public static synchronized void addOnlineCount() {
WebSocketServer.onlineCount++;
}
public static synchronized void subOnlineCount() {
WebSocketServer.onlineCount--;
}
}
- WebSocketController.java 控制層程式碼
package com.springboot.websocket.websocket.controller;
import com.springboot.websocket.websocket.config.WebSocketServer;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import java.io.IOException;
/**
* WebSocketController
*/
@Controller
@RequestMapping("/socket")
public class WebSocketController {
/**
* 輸入訊息的頁面
* @return
*/
@GetMapping("/send")
public String sendMsg(){
return "server";
}
/**
* 推送資料介面
* @Param message
* @return
*/
@RequestMapping("/push")
public String pushMsg(@RequestParam("message")String message) {
try {
WebSocketServer.sendInfo(message);
} catch (IOException e) {
e.printStackTrace();
}
return "server";
}
}
3.3 html頁面程式碼
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>WebSocket</title>
</head>
<body>
<h1>WebScoket練習</h1>
<label>
<input id="msg" type="text" name="message" style="width:215px;" />
<input type="submit" id="btn" />
</label>
<br>
<div>
<ul id="message_show_ul">
</ul>
</div>
<script language="JavaScript">
var send_message = document.getElementById("msg");
var sub_button = document.getElementById("btn");
var show_ul = document.getElementById("message_show_ul");
var socket;
if (typeof(WebSocket) == "undefined") {
console.log("您的瀏覽器不支援WebSocket");
} else {
console.log("您的瀏覽器支援WebSocket");
//實現化WebSocket物件，指定要連線的伺服器地址與埠建立連線
socket = new WebSocket("ws://localhost:8088/websocket");
//開啟事件
socket.onopen = function () {
console.log("Socket已開啟");
sub_button.onclick = function () {
console.log(send_message);
//下面這句話是往伺服器傳送訊息
socket.send("這是來自客戶端的訊息:" + send_message.value);
};
};
//獲得訊息事件，從伺服器獲得訊息
socket.onmessage = function (msg) {
var li_eme = document.createElement("li");
li_eme.innerHTML = msg.data;
show_ul.appendChild(li_eme);
//控制檯列印訊息
console.log(msg.data);
//彈出框彈出訊息
// alert(msg.data);
};
//關閉事件
socket.onclose = function () {
console.log("Socket已關閉");
};
//發生了錯誤事件
socket.onerror = function () {
alert("Socket發生了錯誤");
}
}
</script>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>WebSocketServer</title>
</head>
<body>
<h1>伺服器端</h1>
<form id="login" action="/socket/push" method="get">
<label>
<input id="msg" type="text" name="message" style="width:215px;" />
<input type="submit" id="btn"/>
</label>
<br>
</form>
</body>
</html>
