springboot -- 整合websocket 实现在线聊天

websocket 实现在线聊天效果

pom.xml

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.53</version>
            <scope>compile</scope>
        </dependency>
    </dependencies>

添加 config 配置类

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

@Configuration
public class WebSocketConfig {

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

后端接收处理消息

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;

@Slf4j
@Controller
public class WebSocketController {

    @RequestMapping("/webSocket/{name}")
    public String webSocket(@PathVariable String name, Model model) {
        try {
            log.info("跳转到websocket的页面上");
            model.addAttribute("username", name);
            return "_user";
        } catch (Exception e) {
            log.info("跳转到websocket的页面上发生异常，异常信息是：" + e.getMessage());
            return "error";
        }
    }

    @RequestMapping("/webSocket")
    public String page() {
        try {
            log.info("跳转到总页面上");
            return "ChatRoom";
        } catch (Exception e) {
            log.info("跳转到websocket的页面上发生异常，异常信息是：" + e.getMessage());
            return "error";
        }
    }
}

Socket处理

import com.alibaba.fastjson.JSON;
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.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
@Slf4j
@Component
@ServerEndpoint("/webSocket/{username}")
public class WebSocket {

public static int onlineNumber = 0;
/**
* 以用户的姓名为key，WebSocket为对象保存起来
/
private static Map<String, WebSocket> clients = new ConcurrentHashMap<String, WebSocket>();
/*
* 会话
/
private Session session;
/*
* 用户名称
*/
private String username;

@OnOpen
public void onOpen(@PathParam("username") String username, Session session) {
onlineNumber++;
log.info("现在来连接的客户id：" + session.getId() + "用户名：" + username);
this.username = username;
this.session = session;
log.info("有新连接加入！ 当前在线人数" + onlineNumber);
try {
//messageType 1代表上线 2代表下线 3代表在线名单 4代表普通消息
//先给所有人发送通知，说我上线了
Map<String, Object> map1 = new HashMap<>();
map1.put("messageType", 1);
map1.put("username", username);
sendMessageAll(JSON.toJSONString(map1), username);

//把自己的信息加入到map当中去
clients.put(username, this);
//给自己发一条消息：告诉自己现在都有谁在线
Map<String, Object> map2 = new HashMap<>();
map2.put("messageType", 3);
//移除掉自己
Set set = clients.keySet();
map2.put("onlineUsers", set);
sendMessageTo(JSON.toJSONString(map2), username);
} catch (IOException e) {
log.info(username + "上线的时候通知所有人发生了错误");
}

}

@OnError
public void onError(Session session, Throwable error) {
log.info("服务端发生了错误" + error.getMessage());
//error.printStackTrace();
}

@OnClose
public void onClose() {
onlineNumber--;
//webSockets.remove(this);
clients.remove(username);
try {
//messageType 1代表上线 2代表下线 3代表在线名单 4代表普通消息
Map<String, Object> map1 = new HashMap<>();
map1.put("messageType", 2);
map1.put("onlineUsers", clients.keySet());
map1.put("username", username);
sendMessageAll(JSON.toJSONString(map1), username);
} catch (IOException e) {
log.info(username + "下线的时候通知所有人发生了错误");
}
log.info("有连接关闭！ 当前在线人数" + onlineNumber);
}

@OnMessage
public void onMessage(String message, Session session) {
try {
log.info("来自客户端消息：" + message + "客户端的id是：" + session.getId());
JSONObject jsonObject = JSON.parseObject(message);
String textMessage = jsonObject.getString("message");
String fromusername = jsonObject.getString("username");
String tousername = jsonObject.getString("to");
//如果不是发给所有，那么就发给某一个人
//messageType 1代表上线 2代表下线 3代表在线名单 4代表普通消息
Map<String, Object> map1 = new HashMap<>();
map1.put("messageType", 4);
map1.put("textMessage", textMessage);
map1.put("fromusername", fromusername);
if (tousername.equals("All")) {
map1.put("tousername", "所有人");
sendMessageAll(JSON.toJSONString(map1), fromusername);
} else {
map1.put("tousername", tousername);
sendMessageTo(JSON.toJSONString(map1), tousername);
}
} catch (Exception e) {
log.info("发生了错误了");
}
}

public void sendMessageTo(String message, String ToUserName) throws IOException {
for (WebSocket item : clients.values()) {
if (item.username.equals(ToUserName)) {
item.session.getAsyncRemote().sendText(message);
break;
}
}
}

public void sendMessageAll(String message, String FromUserName) throws IOException {
for (WebSocket item : clients.values()) {
item.session.getAsyncRemote().sendText(message);
}
}

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

}