SpringBoot下使用WebSocket笔记

引入Maven

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
    <version>1.3.5.RELEASE</version>
</dependency>

准备好WebSocket配置类,提供WebSocket出口商Bean.(没有提供将连接不到端点)

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;

/**
 * @Author: HeTongHao
 * @Date: 2019-06-03 18:17
 */
@Configuration
public class WebSocketConfig {
    @Bean
    public ServerEndpointExporter serverEndpointExporter() {
        return new ServerEndpointExporter();
    }
}

定义一个端点

import com.alibaba.fastjson.JSONObject;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

/**
 * @Author: HeTongHao
 * @Date: 2019-06-03 17:20
 */
@Slf4j
@Component
@ServerEndpoint("/webSocket/homeEvent/{username}")
public class WebSocket {
    private static int onlineCount = 0;
    private static Map<String, WebSocket> clients = new ConcurrentHashMap<>();
    private Session session;
    private String username;

    /**
     * 打开连接
     *
     * @param username
     * @param session
     */
    @OnOpen
    public void onOpen(@PathParam("username") String username, Session session) {
        this.username = username;
        this.session = session;
        addOnlineCount();
        clients.put(username, this);
        log.info("{},已连接", username);
    }

    /**
     * 关闭连接回调
     */
    @OnClose
    public void onClose() {
        clients.remove(username);
        subOnlineCount();
    }

    /**
     * 接收消息入口
     *
     * @param message
     */
    @OnMessage
    public void onMessage(String message) {
        JSONObject jsonTo = JSONObject.parseObject(message);
        String mes = (String) jsonTo.get("message");
        if (!jsonTo.get("To").equals("All")) {
            sendMessageTo(mes, jsonTo.get("To").toString());
        } else {
            sendMessageAll("给所有人");
        }
    }

    /**
     * 异常回调
     *
     * @param session
     * @param error
     */
    @OnError
    public void onError(Session session, Throwable error) {
        error.printStackTrace();
    }

    /**
     * 发送消息给某个客户端
     *
     * @param message
     * @param username
     */
    public void sendMessageTo(String message, String username) {
        // session.getBasicRemote().sendText(message);
        for (WebSocket item : clients.values()) {
            if (item.username.equals(username)) {
                item.session.getAsyncRemote().sendText(message);
            }
        }
    }

    /**
     * 发送消息给所有客户端
     *
     * @param message
     */
    public void sendMessageAll(String message) {
        for (WebSocket item : clients.values()) {
            item.session.getAsyncRemote().sendText(message);
        }
    }

    public static synchronized int getOnlineCount() {
        return onlineCount;
    }

    public static synchronized void addOnlineCount() {
        WebSocket.onlineCount++;
    }

    public static synchronized void subOnlineCount() {
        WebSocket.onlineCount--;
    }

    public static synchronized Map<String, WebSocket> getClients() {
        return clients;
    }
}

启动工程就可以通过 ws://127.0.0.1:8082/webSocket/homeEvent/xxx访问了

服务端如果要推送消息给客户端，注入这个端点，调用send相关方法即可.

在线模拟websocket请求工具