[网络协议]webSocket练习

1.简单版

@RequestMapping("/socket")
@RestController
public class MsgController {

    @Autowired
    private MyWebSocketHandler myMessageHandler;

    @RequestMapping("/send1")
    public String sendMessageByUser(@RequestParam String contents) {
        Map<String, WebSocketSession> users = myMessageHandler.getUserMap();

        for(Map.Entry<String, WebSocketSession> map : users.entrySet()){
            try {
                myMessageHandler.handleMessage(map.getValue(), new TextMessage(contents));
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

        return "success";
    }

}

@Component
public class MyWebSocketHandler implements WebSocketHandler {
    public static final String USER_KEY = "socket_user";

    private static final int size = 30;
    private final  Map<String, WebSocketSession> USER_MAP = new HashMap<>();


    //连接成功
    @Override
    public void afterConnectionEstablished(WebSocketSession session) {

        String user_key = getUser(session);
        if(!ObjectUtils.isEmpty(user_key)){
            USER_MAP.put(user_key, session);
        }
    }

    //处理发送消息
    @Override
    public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception {
        String msg = message.toString();
        String userId = this.getUser(session);

        System.out.println("该"+userId+"用户发送的消息是："+msg);
        message = new TextMessage("服务端已经接收到消息，msg="+msg);
        session.sendMessage(message);
    }


    //异常
    @Override
    public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
        WebSocketMessage<String> message = new TextMessage("异常信息："+exception.getMessage());
        session.sendMessage(message);
    }

    //关闭连接
    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception {
        if (session.isOpen()) {
            session.close();
        }
        String userId = this.getUser(session);
        if(!ObjectUtils.isEmpty(userId)){
            USER_MAP.remove(userId);
            System.out.println(userId +"用户已成功关闭会话");
        }else{
            System.out.println("关闭时，获取用户id为空");
        }

    }

    @Override
    public boolean supportsPartialMessages() {
        return false;
    }

    private String getUser(WebSocketSession session) {
        try {
            String uname = session.getAttributes().get(USER_KEY).toString();
            return uname;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    public Map<String, WebSocketSession> getUserMap() {

        return this.USER_MAP;
    }
}

@Configuration
@EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {

    private String path = "/socket";
    @Autowired
    private MyWebSocketHandler socketHandler;

    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry webSocketHandlerRegistry) {

        webSocketHandlerRegistry.addHandler(socketHandler, path).addInterceptors(new WebSocketInterceptor()).setAllowedOrigins("*");

    }
}


public class WebSocketInterceptor extends HttpSessionHandshakeInterceptor {
    @Override
    public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Map<String, Object> attributes) throws Exception {


        if(request instanceof ServletServerHttpRequest){
            HttpServletRequest httpServletRequest = ((ServletServerHttpRequest) request).getServletRequest();
            HttpSession session = httpServletRequest.getSession(true);
            //获取参数
//            String userId = serverHttpRequest.getParameter("userId");
            attributes.put(MyWebSocketHandler.USER_KEY, session.getId());

            return true;
        }
        return true;
    }
}

<!-- websocket -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-websocket</artifactId>
    </dependency>