diff --git a/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java b/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java
index 59b8deb3fb..a338f7b681 100644
--- a/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java
+++ b/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java
@@ -999,11 +999,7 @@ public class DefaultMQPushConsumerImpl implements MQConsumerInner {
 
     @Override
     public Set<SubscriptionData> subscriptions() {
-        Set<SubscriptionData> subSet = new HashSet<SubscriptionData>();
-
-        subSet.addAll(this.rebalanceImpl.getSubscriptionInner().values());
-
-        return subSet;
+        return new HashSet<SubscriptionData>(this.rebalanceImpl.getSubscriptionInner().values());
     }
 
     @Override
diff --git a/client/src/main/java/org/apache/rocketmq/client/impl/producer/DefaultMQProducerImpl.java b/client/src/main/java/org/apache/rocketmq/client/impl/producer/DefaultMQProducerImpl.java
index d08aac4e2b..dfc6de0e75 100644
--- a/client/src/main/java/org/apache/rocketmq/client/impl/producer/DefaultMQProducerImpl.java
+++ b/client/src/main/java/org/apache/rocketmq/client/impl/producer/DefaultMQProducerImpl.java
@@ -273,12 +273,7 @@ public class DefaultMQProducerImpl implements MQProducerInner {
 
     @Override
     public Set<String> getPublishTopicList() {
-        Set<String> topicList = new HashSet<String>();
-        for (String key : this.topicPublishInfoTable.keySet()) {
-            topicList.add(key);
-        }
-
-        return topicList;
+        return new HashSet<String>(this.topicPublishInfoTable.keySet());
     }
 
     @Override