[pinpoint-apm#2993] Server metadata listener notification has a race condition

koo-taejin · koo-taejin · commit f349c7a0df72 · 2017-06-02T15:44:43.000+09:00
use synchronized to prevent race condition
diff --git a/profiler/src/main/java/com/navercorp/pinpoint/profiler/context/DefaultServerMetaDataHolder.java b/profiler/src/main/java/com/navercorp/pinpoint/profiler/context/DefaultServerMetaDataHolder.java
@@ -16,6 +16,10 @@
 
 package com.navercorp.pinpoint.profiler.context;
 
+import com.navercorp.pinpoint.bootstrap.context.ServerMetaData;
+import com.navercorp.pinpoint.bootstrap.context.ServerMetaDataHolder;
+import com.navercorp.pinpoint.bootstrap.context.ServiceInfo;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -25,10 +29,6 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentLinkedQueue;
 
-import com.navercorp.pinpoint.bootstrap.context.ServerMetaData;
-import com.navercorp.pinpoint.bootstrap.context.ServerMetaDataHolder;
-import com.navercorp.pinpoint.bootstrap.context.ServiceInfo;
-
 /**
  * @author hyungil.jeong
  */
@@ -73,7 +73,7 @@ public void removeListener(ServerMetaDataListener listener) {
     }
 
     @Override
-    public void notifyListeners() {
+    public synchronized void notifyListeners() {
         final ServerMetaData serverMetaData = createServerMetaData();
         for (ServerMetaDataListener listener : this.listeners) {
             listener.publishServerMetaData(serverMetaData);
