[improve][broker] Improve the extensibility of the TopicBundleAssignm…

…entStrategy interface class (apache#23773)
rayluoluo · Jan 10, 2025 · dea39e3 · dea39e3
1 parent 04423ba
commit dea39e3
Showing 1 changed file with 12 additions and 2 deletions.
diff --git a/...r/src/main/java/org/apache/pulsar/common/naming/ConsistentHashingTopicBundleAssigner.java b/...r/src/main/java/org/apache/pulsar/common/naming/ConsistentHashingTopicBundleAssigner.java
@@ -28,6 +28,8 @@
 public class ConsistentHashingTopicBundleAssigner implements TopicBundleAssignmentStrategy {
     private PulsarService pulsar;
 
+    private volatile HashFunction hashFunction;
+
     @Override
     public NamespaceBundle findBundle(TopicName topicName, NamespaceBundles namespaceBundles) {
         NamespaceBundle bundle = namespaceBundles.getBundle(calculateBundleHashCode(topicName));
@@ -39,7 +41,14 @@ public NamespaceBundle findBundle(TopicName topicName, NamespaceBundles namespac
 
     @Override
     public long calculateBundleHashCode(TopicName topicName) {
-        return getBundleHashFunc().hashString(topicName.toString(), StandardCharsets.UTF_8).padToLong();
+        if (hashFunction == null) {
+            synchronized (ConsistentHashingTopicBundleAssigner.class) {
+                if (hashFunction == null) {
+                    hashFunction = getBundleHashFunc();
+                }
+            }
+        }
+        return hashFunction.hashString(topicName.toString(), StandardCharsets.UTF_8).padToLong();
     }
 
     @Override
@@ -49,6 +58,7 @@ public void init(PulsarService pulsarService) {
 
     private HashFunction getBundleHashFunc() {
         return Optional.ofNullable(pulsar.getNamespaceService()).map(NamespaceService::getNamespaceBundleFactory)
-                .map(NamespaceBundleFactory::getHashFunc).orElseThrow(() -> new RuntimeException("HashFunc not specified"));
+                .map(NamespaceBundleFactory::getHashFunc)
+                .orElseThrow(() -> new RuntimeException("HashFunc not specified"));
     }
 }