diff --git a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/client/HttpFSFileSystem.java b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/client/HttpFSFileSystem.java
index 055a57ee82..59229586a2 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/client/HttpFSFileSystem.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/client/HttpFSFileSystem.java
@@ -139,7 +139,7 @@ public class HttpFSFileSystem extends FileSystem
 
   public static final String UPLOAD_CONTENT_TYPE= "application/octet-stream";
 
-  public static enum FILE_TYPE {
+  public enum FILE_TYPE {
     FILE, DIRECTORY, SYMLINK;
 
     public static FILE_TYPE getType(FileStatus fileStatus) {
@@ -210,7 +210,7 @@ public static FILE_TYPE getType(FileStatus fileStatus) {
   private static final String HTTP_DELETE = "DELETE";
 
   @InterfaceAudience.Private
-  public static enum Operation {
+  public enum Operation {
     OPEN(HTTP_GET), GETFILESTATUS(HTTP_GET), LISTSTATUS(HTTP_GET),
     GETHOMEDIRECTORY(HTTP_GET), GETCONTENTSUMMARY(HTTP_GET),
     GETFILECHECKSUM(HTTP_GET),  GETFILEBLOCKLOCATIONS(HTTP_GET),
diff --git a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/Server.java b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/Server.java
index 82be027689..57f651a73b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/Server.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/Server.java
@@ -101,7 +101,7 @@ public class Server {
    * Enumeration that defines the server status.
    */
   @InterfaceAudience.Private
-  public static enum Status {
+  public enum Status {
     UNDEF(false, false),
     BOOTING(false, true),
     HALTED(true, true),
diff --git a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/ServerException.java b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/ServerException.java
index e3759ce787..22bfa5fb09 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/ServerException.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/server/ServerException.java
@@ -31,7 +31,7 @@ public class ServerException extends XException {
    * Error codes use by the {@link Server} class.
    */
   @InterfaceAudience.Private
-  public static enum ERROR implements XException.ERROR {
+  public enum ERROR implements XException.ERROR {
     S01("Dir [{0}] does not exist"),
     S02("[{0}] is not a directory"),
     S03("Could not load file from classpath [{0}], {1}"),
diff --git a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/lang/TestXException.java b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/lang/TestXException.java
index 59d02e3d55..2869d47ca8 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/lang/TestXException.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/lang/TestXException.java
@@ -27,7 +27,7 @@
 
 public class TestXException extends HTestCase {
 
-  public static enum TestERROR implements XException.ERROR {
+  public enum TestERROR implements XException.ERROR {
     TC;
 
     @Override
diff --git a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/wsrs/TestParam.java b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/wsrs/TestParam.java
index 92719db7a7..553ce9e43f 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/wsrs/TestParam.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/wsrs/TestParam.java
@@ -100,7 +100,7 @@ public void testLong() throws Exception {
     test(param, "L", "a long", 1L, 2L, "x", null);
   }
 
-  public static enum ENUM {
+  public enum ENUM {
     FOO, BAR
   }
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/OpenFileCtx.java b/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/OpenFileCtx.java
index 9371a72f50..261701973f 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/OpenFileCtx.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/OpenFileCtx.java
@@ -72,7 +72,7 @@ class OpenFileCtx {
   // Pending writes water mark for dump, 1MB
   private static long DUMP_WRITE_WATER_MARK = 1024 * 1024;
 
-  static enum COMMIT_STATUS {
+  enum COMMIT_STATUS {
     COMMIT_FINISHED,
     COMMIT_WAIT,
     COMMIT_INACTIVE_CTX,
diff --git a/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/WriteCtx.java b/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/WriteCtx.java
index f4c32f626a..f89679f073 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/WriteCtx.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/WriteCtx.java
@@ -44,7 +44,7 @@ class WriteCtx {
    * wait for prerequisite writes. NO_DUMP: sequential write, no need to dump
    * since it will be written to HDFS soon. DUMPED: already dumped to a file.
    */
-  public static enum DataState {
+  public enum DataState {
     ALLOW_DUMP,
     NO_DUMP,
     DUMPED
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/LayoutVersion.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/LayoutVersion.java
index 1750790894..671971dc84 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/LayoutVersion.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/LayoutVersion.java
@@ -74,7 +74,7 @@ public interface LayoutFeature {
    * </li>
    * </ul>
    */
-  public static enum Feature implements LayoutFeature {
+  public enum Feature implements LayoutFeature {
     NAMESPACE_QUOTA(-16, "Support for namespace quotas"),
     FILE_ACCESS_TIME(-17, "Support for access time on files"),
     DISKSPACE_QUOTA(-18, "Support for disk space quotas"),
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/CorruptReplicasMap.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/CorruptReplicasMap.java
index 8a097a542c..04425882c3 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/CorruptReplicasMap.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/CorruptReplicasMap.java
@@ -46,7 +46,7 @@
 public class CorruptReplicasMap{
 
   /** The corruption reason code */
-  public static enum Reason {
+  public enum Reason {
     NONE,                // not specified.
     ANY,                 // wildcard reason
     GENSTAMP_MISMATCH,   // mismatch in generation stamps
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeStorageInfo.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeStorageInfo.java
index 8af86d3920..b1ccea2b5c 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeStorageInfo.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeStorageInfo.java
@@ -398,7 +398,7 @@ void setRemainingForTests(int remaining) {
     this.remaining = remaining;
   }
 
-  static enum AddBlockResult {
+  enum AddBlockResult {
     ADDED, REPLACED, ALREADY_EXIST
   }
 }
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BPServiceActor.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BPServiceActor.java
index c1cda5735e..fcf7d5e97a 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BPServiceActor.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BPServiceActor.java
@@ -96,7 +96,7 @@ class BPServiceActor implements Runnable {
   Thread bpThread;
   DatanodeProtocolClientSideTranslatorPB bpNamenode;
 
-  static enum RunningState {
+  enum RunningState {
     CONNECTING, INIT_FAILED, RUNNING, EXITED, FAILED;
   }
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockReceiver.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockReceiver.java
index c5462a96b7..a0e646deca 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockReceiver.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockReceiver.java
@@ -1185,7 +1185,7 @@ private ReplicaHandler claimReplicaHandler() {
     return handler;
   }
 
-  private static enum PacketResponderType {
+  private enum PacketResponderType {
     NON_PIPELINE, LAST_IN_PIPELINE, HAS_DOWNSTREAM_IN_PIPELINE
   }
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNodeLayoutVersion.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNodeLayoutVersion.java
index 609a740cd1..abe7b742f9 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNodeLayoutVersion.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNodeLayoutVersion.java
@@ -61,7 +61,7 @@ public static boolean supports(final LayoutFeature f, final int lv) {
    * </li>
    * </ul>
    */
-  public static enum Feature implements LayoutFeature {
+  public enum Feature implements LayoutFeature {
     FIRST_LAYOUT(-55, -53, "First datanode layout", false),
     BLOCKID_BASED_LAYOUT(-56,
         "The block ID of a finalized block uniquely determines its position " +
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/BackupImage.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/BackupImage.java
index 450ddee9e0..0737824d4e 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/BackupImage.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/BackupImage.java
@@ -55,7 +55,7 @@ public class BackupImage extends FSImage {
    *   stopApplyingOnNextRoll is true.
    */
   volatile BNState bnState;
-  static enum BNState {
+  enum BNState {
     /**
      * Edits from the NN should be dropped. On the next log roll,
      * transition to JOURNAL_ONLY state
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/Content.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/Content.java
index c1caae52ec..cb5a2f4f99 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/Content.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/Content.java
@@ -63,7 +63,7 @@ public Counts newInstance() {
   public static class CountsMap
       extends EnumCounters.Map<CountsMap.Key, Content, Counts> {
     /** The key type of the map. */
-    public static enum Key { CURRENT, SNAPSHOT }
+    public enum Key { CURRENT, SNAPSHOT }
 
     CountsMap() {
       super(FACTORY);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeWithAdditionalFields.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeWithAdditionalFields.java
index 8ff15a8277..fe58577bc4 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeWithAdditionalFields.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INodeWithAdditionalFields.java
@@ -33,7 +33,7 @@
 @InterfaceAudience.Private
 public abstract class INodeWithAdditionalFields extends INode
     implements LinkedElement {
-  static enum PermissionStatusFormat {
+  enum PermissionStatusFormat {
     MODE(null, 16),
     GROUP(MODE.BITS, 25),
     USER(GROUP.BITS, 23);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNode.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNode.java
index 32d268a9db..2bc3642252 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNode.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNode.java
@@ -209,7 +209,7 @@ public class NameNode extends ReconfigurableBase implements
   /**
    * Categories of operations supported by the namenode.
    */
-  public static enum OperationCategory {
+  public enum OperationCategory {
     /** Operations that are state agnostic */
     UNCHECKED,
     /** Read operation that does not change the namespace state */
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeLayoutVersion.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeLayoutVersion.java
index 2943fc2d7e..182cc08b02 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeLayoutVersion.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeLayoutVersion.java
@@ -77,7 +77,7 @@ public static boolean supports(final LayoutFeature f, final int lv) {
    * support downgrade.
    * </ul>
    */
-  public static enum Feature implements LayoutFeature {
+  public enum Feature implements LayoutFeature {
     ROLLING_UPGRADE(-55, -53, -55, "Support rolling upgrade", false),
     EDITLOG_LENGTH(-56, -56, "Add length field to every edit log op"),
     XATTRS(-57, -57, "Extended attributes"),
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/ReceivedDeletedBlockInfo.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/ReceivedDeletedBlockInfo.java
index 740036a042..355f09fff7 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/ReceivedDeletedBlockInfo.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/ReceivedDeletedBlockInfo.java
@@ -28,7 +28,7 @@ public class ReceivedDeletedBlockInfo {
   BlockStatus status;
   String delHints;
 
-  public static enum BlockStatus {
+  public enum BlockStatus {
     RECEIVING_BLOCK(1),
     RECEIVED_BLOCK(2),
     DELETED_BLOCK(3);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineEditsViewer/OfflineEditsXmlLoader.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineEditsViewer/OfflineEditsXmlLoader.java
index 1882e58b3b..a6901f335d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineEditsViewer/OfflineEditsXmlLoader.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineEditsViewer/OfflineEditsXmlLoader.java
@@ -61,7 +61,7 @@ class OfflineEditsXmlLoader
   private long nextTxId;
   private final OpInstanceCache opCache = new OpInstanceCache();
   
-  static enum ParseState {
+  enum ParseState {
     EXPECT_EDITS_TAG,
     EXPECT_VERSION,
     EXPECT_RECORD,
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/util/Diff.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/util/Diff.java
index 54e7103f23..26d1fb577d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/util/Diff.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/util/Diff.java
@@ -73,7 +73,7 @@
  * @param <E> The element type, which must implement {@link Element} interface.
  */
 public class Diff<K, E extends Diff.Element<K>> {
-  public static enum ListType {
+  public enum ListType {
     CREATED, DELETED
   }
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFileCreation.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFileCreation.java
index 9dff529ef7..e191414c96 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFileCreation.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFileCreation.java
@@ -1123,7 +1123,7 @@ public void testCreateNonCanonicalPathAndRestartFromUri()
     doCreateTest(CreationMethod.PATH_FROM_URI);
   }
   
-  private static enum CreationMethod {
+  private enum CreationMethod {
     DIRECT_NN_RPC,
     PATH_FROM_URI,
     PATH_FROM_STRING
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureToReadEdits.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureToReadEdits.java
index 079038c763..38c2b2da4a 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureToReadEdits.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureToReadEdits.java
@@ -82,7 +82,7 @@ public class TestFailureToReadEdits {
   private NameNode nn1;
   private FileSystem fs;
   
-  private static enum TestType {
+  private enum TestType {
     SHARED_DIR_HA,
     QJM_HA;
   };