Отправка сообщения в начале и конце обработки

src/main/java/ru/serega6531/packmate/service/PcapService.java

@@ -4,6 +4,8 @@ import lombok.Getter;
 import org.pcap4j.core.PcapNativeException;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
+import ru.serega6531.packmate.model.enums.SubscriptionMessageType;
+import ru.serega6531.packmate.model.pojo.SubscriptionMessage;
 import ru.serega6531.packmate.pcap.PcapWorker;
 
 @Service
@@ -12,16 +14,19 @@ public class PcapService {
     @Getter
     private boolean started = false;
 
+    private final SubscriptionService subscriptionService;
     private final PcapWorker worker;
 
     @Autowired
-    public PcapService(PcapWorker worker) {
+    public PcapService(SubscriptionService subscriptionService, PcapWorker worker) {
+        this.subscriptionService = subscriptionService;
         this.worker = worker;
     }
 
     public synchronized void start() throws PcapNativeException {
         if(!started) {
             started = true;
+            subscriptionService.broadcast(new SubscriptionMessage(SubscriptionMessageType.PCAP_STARTED, null));
             worker.start();
         }
     }

src/main/java/ru/serega6531/packmate/service/SubscriptionService.java

@@ -2,6 +2,7 @@ package ru.serega6531.packmate.service;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
@@ -39,10 +40,15 @@ public class SubscriptionService {
         log.info("User unsubscribed: {}", Objects.requireNonNull(session.getRemoteAddress()).getHostName());
     }
 
-    void broadcast(SubscriptionMessage message) {
+    /**
+     * Вызов потокобезопасный
+     */
+    @SneakyThrows
+    public void broadcast(SubscriptionMessage message) {
+        final TextMessage messageJson = objectToTextMessage(message);
         subscribers.forEach(s -> {
             try {
-                s.sendMessage(objectToTextMessage(message));
+                s.sendMessage(messageJson);
             } catch (IOException | SockJsTransportFailureException e) {
                 log.warn("WS", e);
             }