給Web端Websocket推送
1、在pom中引入jar包
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</exclusion>
<exclusion>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
2、首先需要引入類WebSocketServerEndpoint，程式碼如下：
package com.zxycloud.service;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;
import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
@ServerEndpoint(value = "/searchTa/websocket")
@Component
public class WebSocketServerEndpoint {
//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。
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。
private static CopyOnWriteArraySet<WebSocketServerEndpoint> webSocketSet = new CopyOnWriteArraySet<WebSocketServerEndpoint>();
//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
private Session session;
protected final Logger logger = LoggerFactory.getLogger(this.getClass());
/**
* 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
logger.info("有新連線加入！當前線上人數為" + getOnlineCount());
try {
sendMessage("連線成功");
} catch (IOException e) {
logger.error("websocket IO異常");
}
}
// //連線開啟時執行
// @OnOpen
// public void onOpen(@PathParam("user") String user, Session session) {
// currentUser = user;
// System.out.println("Connected ... " + session.getId());
// }
/**
* 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
logger.info("有一連線關閉！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) {
logger.info("來自客戶端的訊息:" + message);
//群發訊息
/* for (WebSocketServerEndpoint item : webSocketSet) {
try {
item.sendMessage(message);
} catch (IOException e) {
e.printStackTrace();
}
}*/
}
/**
*
* @param session
* @param error
*/
@OnError
public void onError(Session session, Throwable error) {
logger.error("發生錯誤");
error.printStackTrace();
}
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 {
//logger.info(message);
for (WebSocketServerEndpoint item : webSocketSet) {
try {
item.sendMessage(message);
} catch (IOException e) {
continue;
}
}
}
public static synchronized int getOnlineCount() {
return onlineCount;
}
public static synchronized void addOnlineCount() {
WebSocketServerEndpoint.onlineCount++;
}
public static synchronized void subOnlineCount() {
WebSocketServerEndpoint.onlineCount--;
}
}
3、在想要給前端傳送訊息的地方呼叫WebSocketServerEndpoint的sendInfo方法
JSONObject jsonobject = new JSONObject();
jsonobject.put("address", address);
jsonobject.put("createTime", String.valueOf(json.get("msgCreateTime")));
jsonobject.put("deviceid", deviceid);
try {
WebSocketServerEndpoint.sendInfo(jsonobject.toString());
logger.info("WebSocke連線成功！");
}catch (IOException e) {
logger.info("WebSocke連線失敗！");
}
前端監控著/searchTa/websocket這個地址，有訊息過來就會顯示推送。