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Author: aaron-ai

java/client/src/main/java/org/apache/rocketmq/client/java/impl/consumer/PullConsumerImpl.java

@@ -275,9 +275,13 @@ public void assign(Collection<MessageQueue> mqs) {
 
     void assign(Map<MessageQueue, FilterExpression> subscriptions) {
         assign0(subscriptions);
+        // Notify the scanner to scan the assigned queue immediately.
         scanner.signal();
     }
 
+    /**
+     * Replace the current subscriptions with the latest subscriptions.
+     */
     void assign0(Map<MessageQueue, FilterExpression> subscriptions) {
         checkNotNull(subscriptions, "subscriptions to be assigned should not be null");
         checkArgument(!subscriptions.isEmpty(), "subscription should not be empty");
@@ -502,7 +506,7 @@ protected void startUp() throws Exception {
                 try {
                     commit();
                 } catch (Throwable t) {
-                    log.error("Failed to commit offset, clientId={}", clientId, t);
+                    log.error("Failed to commit offset for pull consumer, clientId={}", clientId, t);
                 }
             }, AUTO_COMMIT_DELAY.toNanos(), autoCommitInterval.toNanos(), TimeUnit.NANOSECONDS);
         }
@@ -560,7 +564,6 @@ public void onTopicRouteDataUpdate0(String topic, TopicRouteData topicRouteData)
     public void doStats() {
         final long pullTimes = this.pullTimes.getAndSet(0);
         final long pulledMessagesQuantity = this.pulledMessagesQuantity.getAndSet(0);
-
         log.info("clientId={}, consumerGroup={}, pullTimes={}, pulledMessageQuantity={}", clientId, consumerGroup,
             pullTimes, pulledMessagesQuantity);
         processQueueTable.values().forEach(ProcessQueue::doStats);