diff --git a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/Quota.java b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/Quota.java
index 5d0309fa57..cfb538f8f6 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/Quota.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/Quota.java
@@ -163,7 +163,7 @@ private QuotaUsage aggregateQuota(Map<RemoteLocation, QuotaUsage> results) {
     long ssCount = 0;
     long nsQuota = HdfsConstants.QUOTA_RESET;
     long ssQuota = HdfsConstants.QUOTA_RESET;
-    boolean hasQuotaUnSet = false;
+    boolean hasQuotaUnset = false;
 
     for (Map.Entry<RemoteLocation, QuotaUsage> entry : results.entrySet()) {
       RemoteLocation loc = entry.getKey();
@@ -172,7 +172,7 @@ private QuotaUsage aggregateQuota(Map<RemoteLocation, QuotaUsage> results) {
         // If quota is not set in real FileSystem, the usage
         // value will return -1.
         if (usage.getQuota() == -1 && usage.getSpaceQuota() == -1) {
-          hasQuotaUnSet = true;
+          hasQuotaUnset = true;
         }
         nsQuota = usage.getQuota();
         ssQuota = usage.getSpaceQuota();
@@ -189,7 +189,7 @@ private QuotaUsage aggregateQuota(Map<RemoteLocation, QuotaUsage> results) {
 
     QuotaUsage.Builder builder = new QuotaUsage.Builder()
         .fileAndDirectoryCount(nsCount).spaceConsumed(ssCount);
-    if (hasQuotaUnSet) {
+    if (hasQuotaUnset) {
       builder.quota(HdfsConstants.QUOTA_RESET)
           .spaceQuota(HdfsConstants.QUOTA_RESET);
     } else {
diff --git a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterClientProtocol.java b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterClientProtocol.java
index c52b765565..13f8f37749 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterClientProtocol.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterClientProtocol.java
@@ -20,7 +20,7 @@
 import static org.apache.hadoop.hdfs.server.federation.router.FederationUtil.updateMountPointStatus;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.crypto.CryptoProtocolVersion;
-import org.apache.hadoop.fs.BatchedRemoteIterator;
+import org.apache.hadoop.fs.BatchedRemoteIterator.BatchedEntries;
 import org.apache.hadoop.fs.CacheFlag;
 import org.apache.hadoop.fs.ContentSummary;
 import org.apache.hadoop.fs.CreateFlag;
@@ -1147,7 +1147,7 @@ public void removeCacheDirective(long id) throws IOException {
   }
 
   @Override
-  public BatchedRemoteIterator.BatchedEntries<CacheDirectiveEntry> listCacheDirectives(
+  public BatchedEntries<CacheDirectiveEntry> listCacheDirectives(
       long prevId, CacheDirectiveInfo filter) throws IOException {
     rpcServer.checkOperation(NameNode.OperationCategory.READ, false);
     return null;
@@ -1169,7 +1169,7 @@ public void removeCachePool(String cachePoolName) throws IOException {
   }
 
   @Override
-  public BatchedRemoteIterator.BatchedEntries<CachePoolEntry> listCachePools(String prevKey)
+  public BatchedEntries<CachePoolEntry> listCachePools(String prevKey)
       throws IOException {
     rpcServer.checkOperation(NameNode.OperationCategory.READ, false);
     return null;
@@ -1280,7 +1280,7 @@ public EncryptionZone getEZForPath(String src) throws IOException {
   }
 
   @Override
-  public BatchedRemoteIterator.BatchedEntries<EncryptionZone> listEncryptionZones(long prevId)
+  public BatchedEntries<EncryptionZone> listEncryptionZones(long prevId)
       throws IOException {
     rpcServer.checkOperation(NameNode.OperationCategory.READ, false);
     return null;
@@ -1293,7 +1293,7 @@ public void reencryptEncryptionZone(String zone, HdfsConstants.ReencryptAction a
   }
 
   @Override
-  public BatchedRemoteIterator.BatchedEntries<ZoneReencryptionStatus> listReencryptionStatus(
+  public BatchedEntries<ZoneReencryptionStatus> listReencryptionStatus(
       long prevId) throws IOException {
     rpcServer.checkOperation(NameNode.OperationCategory.READ, false);
     return null;
@@ -1529,15 +1529,17 @@ public ReplicatedBlockStats getReplicatedBlockStats() throws IOException {
 
   @Deprecated
   @Override
-  public BatchedRemoteIterator.BatchedEntries<OpenFileEntry> listOpenFiles(long prevId)
+  public BatchedEntries<OpenFileEntry> listOpenFiles(long prevId)
       throws IOException {
-    return listOpenFiles(prevId, EnumSet.of(OpenFilesIterator.OpenFilesType.ALL_OPEN_FILES),
+    return listOpenFiles(prevId,
+        EnumSet.of(OpenFilesIterator.OpenFilesType.ALL_OPEN_FILES),
         OpenFilesIterator.FILTER_PATH_DEFAULT);
   }
 
   @Override
-  public BatchedRemoteIterator.BatchedEntries<OpenFileEntry> listOpenFiles(long prevId,
-      EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes, String path) throws IOException {
+  public BatchedEntries<OpenFileEntry> listOpenFiles(long prevId,
+      EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes, String path)
+          throws IOException {
     rpcServer.checkOperation(NameNode.OperationCategory.READ, false);
     return null;
   }
@@ -1669,7 +1671,7 @@ private HdfsFileStatus getFileInfoAll(final List<RemoteLocation> locations,
     // Get the file info from everybody
     Map<RemoteLocation, HdfsFileStatus> results =
         rpcClient.invokeConcurrent(locations, method, HdfsFileStatus.class);
-    int children=0;
+    int children = 0;
     // We return the first file
     HdfsFileStatus dirStatus = null;
     for (RemoteLocation loc : locations) {
diff --git a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaManager.java b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaManager.java
index fa2a6e43fa..e818f5accd 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaManager.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaManager.java
@@ -88,7 +88,7 @@ public RouterQuotaUsage getQuotaUsage(String path) {
   }
 
   /**
-   * Get children paths (can including itself) under specified federation path.
+   * Get children paths (can include itself) under specified federation path.
    * @param parentPath Federated path.
    * @return Set of children paths.
    */
diff --git a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUpdateService.java b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUpdateService.java
index 9bfd705efb..dd21e1a7e6 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUpdateService.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUpdateService.java
@@ -186,10 +186,8 @@ private List<MountTable> getMountTableEntries() throws IOException {
    */
   private List<MountTable> getQuotaSetMountTables() throws IOException {
     List<MountTable> mountTables = getMountTableEntries();
-    Set<String> stalePaths = new HashSet<>();
-    for (String path : this.quotaManager.getAll()) {
-      stalePaths.add(path);
-    }
+    Set<String> allPaths = this.quotaManager.getAll();
+    Set<String> stalePaths = new HashSet<>(allPaths);
 
     List<MountTable> neededMountTables = new LinkedList<>();
     for (MountTable entry : mountTables) {
diff --git a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUsage.java b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUsage.java
index de9119aed4..7fd845af76 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUsage.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterQuotaUsage.java
@@ -75,9 +75,10 @@ public Builder spaceQuota(long spaceQuota) {
    * @throws NSQuotaExceededException If the quota is exceeded.
    */
   public void verifyNamespaceQuota() throws NSQuotaExceededException {
-    if (Quota.isViolated(getQuota(), getFileAndDirectoryCount())) {
-      throw new NSQuotaExceededException(getQuota(),
-          getFileAndDirectoryCount());
+    long quota = getQuota();
+    long fileAndDirectoryCount = getFileAndDirectoryCount();
+    if (Quota.isViolated(quota, fileAndDirectoryCount)) {
+      throw new NSQuotaExceededException(quota, fileAndDirectoryCount);
     }
   }
 
@@ -87,25 +88,29 @@ public void verifyNamespaceQuota() throws NSQuotaExceededException {
    * @throws DSQuotaExceededException If the quota is exceeded.
    */
   public void verifyStoragespaceQuota() throws DSQuotaExceededException {
-    if (Quota.isViolated(getSpaceQuota(), getSpaceConsumed())) {
-      throw new DSQuotaExceededException(getSpaceQuota(), getSpaceConsumed());
+    long spaceQuota = getSpaceQuota();
+    long spaceConsumed = getSpaceConsumed();
+    if (Quota.isViolated(spaceQuota, spaceConsumed)) {
+      throw new DSQuotaExceededException(spaceQuota, spaceConsumed);
     }
   }
 
   @Override
   public String toString() {
-    String nsQuota = String.valueOf(getQuota());
-    String nsCount = String.valueOf(getFileAndDirectoryCount());
-    if (getQuota() == HdfsConstants.QUOTA_RESET) {
-      nsQuota = "-";
-      nsCount = "-";
+    String nsQuota = "-";
+    String nsCount = "-";
+    long quota = getQuota();
+    if (quota != HdfsConstants.QUOTA_RESET) {
+      nsQuota = String.valueOf(quota);
+      nsCount = String.valueOf(getFileAndDirectoryCount());
     }
 
-    String ssQuota = StringUtils.byteDesc(getSpaceQuota());
-    String ssCount = StringUtils.byteDesc(getSpaceConsumed());
-    if (getSpaceQuota() == HdfsConstants.QUOTA_RESET) {
-      ssQuota = "-";
-      ssCount = "-";
+    String ssQuota = "-";
+    String ssCount = "-";
+    long spaceQuota = getSpaceQuota();
+    if (spaceQuota != HdfsConstants.QUOTA_RESET) {
+      ssQuota = StringUtils.byteDesc(spaceQuota);
+      ssCount = StringUtils.byteDesc(getSpaceConsumed());
     }
 
     StringBuilder str = new StringBuilder();