diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPullConsumer.java b/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPullConsumer.java
index a8dd766ae3d797444ae085d1e78401b653e68782..aac420748ad05194c226670e9f680ce8f17d7f98 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPullConsumer.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPullConsumer.java
@@ -335,6 +335,7 @@ public class DefaultMQPullConsumer extends ClientConfig implements MQPullConsume
             MessageDecoder.decodeMessageId(uniqKey);
             return this.viewMessage(uniqKey);
         } catch (Exception e) {
+            // Ignore
         }
         return this.defaultMQPullConsumerImpl.queryMessageByUniqKey(topic, uniqKey);
     }
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java b/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java
index 38c4649f8cb2fab9b893b983563c359208c6dfb2..2575827d84f49afe5e5903896def905fe1b7ae1f 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java
@@ -210,6 +210,7 @@ public class DefaultMQPushConsumer extends ClientConfig implements MQPushConsume
             MessageDecoder.decodeMessageId(msgId);
             return this.viewMessage(msgId);
         } catch (Exception e) {
+            // Ignore
         }
         return this.defaultMQPushConsumerImpl.queryMessageByUniqKey(topic, msgId);
     }
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/PullCallback.java b/client/src/main/java/org/apache/rocketmq/client/consumer/PullCallback.java
index fd2be0ef208b88dab64f462c17f175c5d20bd7cf..508050dc6133fc59ba9ceb902766195286caa09a 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/PullCallback.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/PullCallback.java
@@ -22,7 +22,7 @@ package org.apache.rocketmq.client.consumer;
  * @author vintagewang@apache.org
  */
 public interface PullCallback {
-    public void onSuccess(final PullResult pullResult);
+    void onSuccess(final PullResult pullResult);
 
-    public void onException(final Throwable e);
+    void onException(final Throwable e);
 }
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/PullTaskCallback.java b/client/src/main/java/org/apache/rocketmq/client/consumer/PullTaskCallback.java
index f0e9b25216c26dba6e8642d9cb614aa600bf8fd2..dc74bcabea963695378c85c4920ccdbd5d03b099 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/PullTaskCallback.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/PullTaskCallback.java
@@ -20,5 +20,5 @@ import org.apache.rocketmq.common.message.MessageQueue;
 
 
 public interface PullTaskCallback {
-    public void doPullTask(final MessageQueue mq, final PullTaskContext context);
+    void doPullTask(final MessageQueue mq, final PullTaskContext context);
 }
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/listener/ConsumeReturnType.java b/client/src/main/java/org/apache/rocketmq/client/consumer/listener/ConsumeReturnType.java
index 82570ab3400c0c5372bc111eeb1bd0890c6d8db8..99083b4c832c22dba6b306cf3395f306bec4c7b8 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/listener/ConsumeReturnType.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/listener/ConsumeReturnType.java
@@ -17,9 +17,6 @@
 
 package org.apache.rocketmq.client.consumer.listener;
 
-/**
- * Created by alvin on 16-11-30.
- */
 public enum ConsumeReturnType {
     /**
      * consume return success
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/rebalance/AllocateMessageQueueByMachineRoom.java b/client/src/main/java/org/apache/rocketmq/client/consumer/rebalance/AllocateMessageQueueByMachineRoom.java
index d3448c9cddfc86b6ee564df5cab731537eb1abd7..adfc124b2942d79c5a323c68944e500ddf60199e 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/rebalance/AllocateMessageQueueByMachineRoom.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/rebalance/AllocateMessageQueueByMachineRoom.java
@@ -45,12 +45,12 @@ public class AllocateMessageQueueByMachineRoom implements AllocateMessageQueueSt
                 premqAll.add(mq);
             }
         }
-        // Todo cid
+
         int mod = premqAll.size() / cidAll.size();
         int rem = premqAll.size() % cidAll.size();
-        int startindex = mod * currentIndex;
-        int endindex = startindex + mod;
-        for (int i = startindex; i < endindex; i++) {
+        int startIndex = mod * currentIndex;
+        int endIndex = startIndex + mod;
+        for (int i = startIndex; i < endIndex; i++) {
             result.add(mqAll.get(i));
         }
         if (rem > currentIndex) {
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java b/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java
index 4fd691110451391fd1b0974355c1da4b8cb941ba..de9d0ddfe06b99ed162d5df60bc81ffbbc6719bf 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java
@@ -125,7 +125,7 @@ public class RemoteBrokerOffsetStore implements OffsetStore {
             return;
 
         final HashSet<MessageQueue> unusedMQ = new HashSet<MessageQueue>();
-        if (mqs != null && !mqs.isEmpty()) {
+        if (!mqs.isEmpty()) {
             for (Map.Entry<MessageQueue, AtomicLong> entry : this.offsetTable.entrySet()) {
                 MessageQueue mq = entry.getKey();
                 AtomicLong offset = entry.getValue();
diff --git a/client/src/main/java/org/apache/rocketmq/client/hook/CheckForbiddenHook.java b/client/src/main/java/org/apache/rocketmq/client/hook/CheckForbiddenHook.java
index 41ed088f5e1ae814d640ff331bd881975e906300..90f164b0f7b4c0cdf67f6a9e8f0f74bacb26ef9e 100644
--- a/client/src/main/java/org/apache/rocketmq/client/hook/CheckForbiddenHook.java
+++ b/client/src/main/java/org/apache/rocketmq/client/hook/CheckForbiddenHook.java
@@ -24,8 +24,8 @@ import org.apache.rocketmq.client.exception.MQClientException;
  * @author manhong.yqd
  */
 public interface CheckForbiddenHook {
-    public String hookName();
+    String hookName();
 
 
-    public void checkForbidden(final CheckForbiddenContext context) throws MQClientException;
+    void checkForbidden(final CheckForbiddenContext context) throws MQClientException;
 }
diff --git a/client/src/main/java/org/apache/rocketmq/client/hook/FilterMessageHook.java b/client/src/main/java/org/apache/rocketmq/client/hook/FilterMessageHook.java
index 016ff56cf1377a04b80bf9f691b4565a96ca58b6..28956ee991a59648ee7e8ada57197b4e665dde58 100644
--- a/client/src/main/java/org/apache/rocketmq/client/hook/FilterMessageHook.java
+++ b/client/src/main/java/org/apache/rocketmq/client/hook/FilterMessageHook.java
@@ -20,8 +20,8 @@ package org.apache.rocketmq.client.hook;
  * @author manhong.yqd
  */
 public interface FilterMessageHook {
-    public String hookName();
+    String hookName();
 
 
-    public void filterMessage(final FilterMessageContext context);
+    void filterMessage(final FilterMessageContext context);
 }