后端学习笔记-WebSocket

介绍

入门实现

入门

配置类

package com.sky.config;

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

/**
 * WebSocket配置类，用于注册WebSocket的Bean
 */
@Configuration
public class WebSocketConfiguration {

    @Bean
    public ServerEndpointExporter serverEndpointExporter() {
        return new ServerEndpointExporter();
    }

}

服务类

package com.sky.websocket;

import org.springframework.stereotype.Component;
import javax.websocket.OnClose;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

/**
 * WebSocket服务
 */
@Component
@ServerEndpoint("/ws/{sid}")
public class WebSocketServer {

    //存放会话对象
    private static Map<String, Session> sessionMap = new HashMap();

    /**
     * 连接建立成功调用的方法
     */
    @OnOpen
    public void onOpen(Session session, @PathParam("sid") String sid) {
        System.out.println("客户端：" + sid + "建立连接");
        sessionMap.put(sid, session);
    }

    /**
     * 收到客户端消息后调用的方法
     *
     * @param message 客户端发送过来的消息
     */
    @OnMessage
    public void onMessage(String message, @PathParam("sid") String sid) {
        System.out.println("收到来自客户端：" + sid + "的信息:" + message);
    }

    /**
     * 连接关闭调用的方法
     *
     * @param sid
     */
    @OnClose
    public void onClose(@PathParam("sid") String sid) {
        System.out.println("连接断开:" + sid);
        sessionMap.remove(sid);
    }

    /**
     * 群发
     *
     * @param message
     */
    public void sendToAllClient(String message) {
        Collection<Session> sessions = sessionMap.values();
        for (Session session : sessions) {
            try {
                //服务器向客户端发送消息
                session.getBasicRemote().sendText(message);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

}

调用广播方法

@Component
public class WebSocketTask {
    @Autowired
    private WebSocketServer webSocketServer;

    /**
     * 通过WebSocket每隔5秒向客户端发送消息
     */
    @Scheduled(cron = "0/5 * * * * ?")
    public void sendMessageToClient() {
        webSocketServer.sendToAllClient("这是来自服务端的消息：" + DateTimeFormatter.ofPattern("HH:mm:ss").format(LocalDateTime.now()));
    }
}

需求

在支付成功的回调接口里面添加向客户端发送消息的逻辑完成来单提醒

/**
     * 支付成功，修改订单状态
     *
     * @param outTradeNo
     */
    public void paySuccess(String outTradeNo) {

        // 根据订单号查询订单
        Orders ordersDB = orderMapper.getByNumber(outTradeNo);

        // 根据订单id更新订单的状态、支付方式、支付状态、结账时间
        Orders orders = Orders.builder()
                .id(ordersDB.getId())
                .status(Orders.TO_BE_CONFIRMED)
                .payStatus(Orders.PAID)
                .checkoutTime(LocalDateTime.now())
                .build();

        orderMapper.update(orders);

        // 通过ws向客户端发送推送消息 type orderId content
        Map map = new HashMap<>();
        map.put("type", 1);
        map.put("orderId", ordersDB.getId());
        map.put("content", "订单号:"+ outTradeNo);
        String json = JSON.toJSONString(map);
        webSocketServer.sendToAllClient(json);
    }

催单同理

/**
     * 催单
     * @param id
     */
    public void reminder(Long id) {
        Orders orders = orderMapper.getById(id);
        if(orders == null){
            throw new OrderBusinessException(MessageConstant.ORDER_NOT_FOUND);
        }
        if(orders.getStatus() != Orders.TO_BE_CONFIRMED){
            throw new OrderBusinessException(MessageConstant.ORDER_STATUS_ERROR);
        }
        //通过ws发送消息给管理端
        Map map = new HashMap();
        map.put("type", 2);
        map.put("orderId", id);
        map.put("content", "订单号：" + orders.getNumber());

        String json = JSON.toJSONString(map);

        webSocketServer.sendToAllClient(json);
    }