From 5cb968810b4b3d3408ac12873b418d7b9562a01e Mon Sep 17 00:00:00 2001
From: Sergey Ponomarev <stokito@gmail.com>
Date: Wed, 3 Dec 2025 19:16:33 +0200
Subject: [PATCH] sip plugin: Call make listeners final and use addIfAbsent

---
 plugins/sip/src/main/java/net/java/sipmack/sip/Call.java | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/plugins/sip/src/main/java/net/java/sipmack/sip/Call.java b/plugins/sip/src/main/java/net/java/sipmack/sip/Call.java
index 9e52ca6ca..e5ea1720e 100644
--- a/plugins/sip/src/main/java/net/java/sipmack/sip/Call.java
+++ b/plugins/sip/src/main/java/net/java/sipmack/sip/Call.java
@@ -99,7 +99,7 @@ public class Call implements ReceiveStreamListener {
     private String callState = "";
 
     // Event Management
-    List<CallListener> listeners = new CopyOnWriteArrayList<CallListener>();
+    private final CopyOnWriteArrayList<CallListener> listeners = new CopyOnWriteArrayList<CallListener>();
     
     public SessionDescription getLocalSdpDescription() {
         return localSdpDescription;
@@ -316,7 +316,7 @@ public class Call implements ReceiveStreamListener {
     // ====================== EVENTS ===========================
     public void addStateChangeListener(CallListener listener) {
         Log.debug(listener.getClass().getCanonicalName());
-        listeners.add(listener);
+        listeners.addIfAbsent(listener);
     }
 
     public void fireCallStatusChangedEvent(String oldStatus) {
@@ -356,4 +356,4 @@ public class Call implements ReceiveStreamListener {
     public void update(ReceiveStreamEvent receiveStreamEvent) {
 
     }
-}
\ No newline at end of file
+}