chat-demo/src/main/java/com/zhangshu/chat/demo/websocket/ChatRoom.java

package com.zhangshu.chat.demo.websocket;

import cn.hutool.cache.Cache;
import cn.hutool.cache.CacheUtil;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.zhangshu.chat.demo.entity.Room;
import com.zhangshu.chat.demo.service.RoomCache;
import com.zhangshu.chat.demo.vo.RoomUserVo;
import com.zhangshu.chat.demo.vo.UserMessageVo;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.Objects;
import java.util.Optional;

@Slf4j
@Component
@ServerEndpoint("/chat/room/{userId}")
public class ChatRoom {
    private final Cache<String, Long> sessionUserCache = CacheUtil.newFIFOCache(16);
    private final Cache<String, Session> sessionCache = CacheUtil.newFIFOCache(16);
    private final Cache<Long, String> userSessionCache = CacheUtil.newFIFOCache(16);
    @Autowired
    RoomCache roomCache;
    @Autowired
    ObjectMapper objectMapper;

    /**
     * 建立连接
     *
     * @param session 客户端连接对象
     */
    @OnOpen
    public void onOpen(Session session, @PathParam("userId") Long userId) {
        if (!roomCache.isExistUser(userId)) {
            sendMessage("用户不在房间中，拒绝连接", session);
            return;
        }
        String sessionId = session.getId().toLowerCase();
        sessionUserCache.put(sessionId, userId);
        sessionCache.put(sessionId, session);
        userSessionCache.put(userId, sessionId);
        log.info("客户端连接建立成功，User ID：{}，当前在线数：{}", userId, sessionUserCache.size());
    }

    /**
     * 接收客户端消息
     *
     * @param message 客户端发送的消息内容
     * @param session 客户端连接对象
     */
    @OnMessage
    @SneakyThrows
    public void onMessage(String message, Session session) {
        log.info("服务端接收消息成功，消息内容：{}", message);
        // 处理消息，并响应给客户端
        String sessionId = session.getId().toLowerCase();
        Long userId = sessionUserCache.get(sessionId);
        if (Objects.isNull(userId)) {
            return;
        }
        Room room = roomCache.getRoomByUser(userId);
        if (Objects.isNull(room)) {
            return;
        }
        Optional<RoomUserVo> userVo = room.getUserList().stream().filter(v -> v.getId().equals(userId)).findFirst();
        if (!userVo.isPresent()) {
            return;
        }
        UserMessageVo messageVo = UserMessageVo.builder()
                .id(userId)
                .nickname(userVo.get().getNickname())
                .username(userVo.get().getUsername())
                .message(message)
                .build();
        String text = objectMapper.writeValueAsString(messageVo);
        room.getUserList().stream()
                .map(RoomUserVo::getId)
                .map(userSessionCache::get)
                .map(sessionCache::get)
                .forEach(v -> {
                    this.sendMessage(text, v);
                });
        log.info("服务端响应消息成功，接收的User ID：{}，响应内容：{}", userId, text);
    }

    /**
     * 处理消息，并响应给客户端
     *
     * @param message 发送的消息内容
     * @param session 发送对象
     */

    private void sendMessage(String message, Session session) {
        try {
            session.getBasicRemote().sendText(message);
        } catch (IOException e) {
            log.error("服务端响应消息异常：{}", e.getMessage());
        }

    }

    /**
     * 关闭连接
     *
     * @param session 客户端连接对象
     */
    @OnClose
    public void onClose(Session session) {
        String sessionId = session.getId().toLowerCase();
        Long userId = sessionUserCache.get(sessionId);
        sessionUserCache.remove(sessionId);
        sessionCache.remove(sessionId);
        userSessionCache.remove(userId);
        log.info("客户端连接关闭成功，User ID：{}，当前在线数：{}", userId, sessionUserCache.size());
    }

    /**
     * 连接异常
     *
     * @param session 客户端连接对象
     * @param error   异常
     */
    @OnError
    public void onError(Session session, Throwable error) {
        String sessionId = session.getId().toLowerCase();
        Long userId = sessionUserCache.get(sessionId);
        sessionUserCache.remove(sessionId);
        sessionCache.remove(sessionId);
        userSessionCache.remove(userId);
        log.info("连接异常，User ID：{},error:{}", userId, error);
    }
}