Fix the wrong parameter in the log.
### Motivation
Bad parameters in the log will always print "null", which can confuse users.
### Modifications
Correct exception parameter.
@@ -340,7 +340,7 @@ public class SystemTopicBasedTopicPoliciesService implements TopicPoliciesServic
reader.readNextAsync().whenComplete((msg, e) -> {
if (e != null) {
log.error("[{}] Failed to read event from the system topic.",
- reader.getSystemTopic().getTopicName(), ex);
+ reader.getSystemTopic().getTopicName(), e);
future.completeExceptionally(e);
readerCaches.remove(reader.getSystemTopic().getTopicName().getNamespaceObject());
policyCacheInitMap.remove(reader.getSystemTopic().getTopicName().getNamespaceObject());
