HDFS-2241. Remove implementing FSConstants interface to just get the constants from the interface. Contributed by Suresh Srinivas.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1156420 13f79535-47bb-0310-9956-ffa450edef68

hdfs/CHANGES.txt

@@ -657,6 +657,9 @@ Trunk (unreleased changes)
     HDFS-2239. Reduce access levels of the fields and methods in FSNamesystem.
     (szetszwo)
 
+    HDFS-2241. Remove implementing FSConstants interface to just get the
+    constants from the interface. (suresh)
+
   OPTIMIZATIONS
 
     HDFS-1458. Improve checkpoint performance by avoiding unnecessary image

hdfs/src/java/org/apache/hadoop/hdfs/DFSClient.java

@@ -61,6 +61,9 @@ import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.DirectoryListing;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.FSConstants;
+import org.apache.hadoop.hdfs.protocol.FSConstants.DatanodeReportType;
+import org.apache.hadoop.hdfs.protocol.FSConstants.SafeModeAction;
+import org.apache.hadoop.hdfs.protocol.FSConstants.UpgradeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
 import org.apache.hadoop.hdfs.protocol.HdfsProtoUtil;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
@@ -106,7 +109,7 @@ import org.apache.hadoop.util.Progressable;
  *
  ********************************************************/
 @InterfaceAudience.Private
-public class DFSClient implements FSConstants, java.io.Closeable {
+public class DFSClient implements java.io.Closeable {
   public static final Log LOG = LogFactory.getLog(DFSClient.class);
   public static final long SERVER_DEFAULTS_VALIDITY_PERIOD = 60 * 60 * 1000L; // 1 hour
   static final int TCP_WINDOW_SIZE = 128 * 1024; // 128 KB
@@ -165,7 +168,7 @@ public class DFSClient implements FSConstants, java.io.Closeable {
       writePacketSize = conf.getInt(DFS_CLIENT_WRITE_PACKET_SIZE_KEY,
           DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT);
       defaultBlockSize = conf.getLong(DFS_BLOCK_SIZE_KEY,
-          DEFAULT_BLOCK_SIZE);
+          DFS_BLOCK_SIZE_DEFAULT);
       defaultReplication = (short) conf.getInt(
           DFS_REPLICATION_KEY, DFS_REPLICATION_DEFAULT);
       taskId = conf.get("mapreduce.task.attempt.id", "NONMAPREDUCE");
@@ -1043,7 +1046,7 @@ public class DFSClient implements FSConstants, java.io.Closeable {
 
           out = new DataOutputStream(
               new BufferedOutputStream(NetUtils.getOutputStream(sock), 
-                                       DataNode.SMALL_BUFFER_SIZE));
+                                       FSConstants.SMALL_BUFFER_SIZE));
           in = new DataInputStream(NetUtils.getInputStream(sock));
 
           if (LOG.isDebugEnabled()) {

hdfs/src/java/org/apache/hadoop/hdfs/DFSConfigKeys.java

@@ -234,7 +234,7 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
   public static final String  DFS_DF_INTERVAL_KEY = "dfs.df.interval";
   public static final int     DFS_DF_INTERVAL_DEFAULT = 60000;
   public static final String  DFS_BLOCKREPORT_INTERVAL_MSEC_KEY = "dfs.blockreport.intervalMsec";
-  public static final long    DFS_BLOCKREPORT_INTERVAL_MSEC_DEFAULT = 21600000;
+  public static final long    DFS_BLOCKREPORT_INTERVAL_MSEC_DEFAULT = 60 * 60 * 1000;
   public static final String  DFS_BLOCKREPORT_INITIAL_DELAY_KEY = "dfs.blockreport.initialDelay";
   public static final int     DFS_BLOCKREPORT_INITIAL_DELAY_DEFAULT = 0;
   public static final String  DFS_BLOCK_INVALIDATE_LIMIT_KEY = "dfs.block.invalidate.limit";

hdfs/src/java/org/apache/hadoop/hdfs/DFSOutputStream.java

@@ -48,6 +48,7 @@ import org.apache.hadoop.hdfs.protocol.ClientProtocol;
 import org.apache.hadoop.hdfs.protocol.DSQuotaExceededException;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
+import org.apache.hadoop.hdfs.protocol.FSConstants;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
 import org.apache.hadoop.hdfs.protocol.HdfsProtoUtil;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
@@ -167,7 +168,7 @@ class DFSOutputStream extends FSOutputSummer implements Syncable {
       this.seqno = HEART_BEAT_SEQNO;
       
       buffer = null;
-      int packetSize = PacketHeader.PKT_HEADER_LEN + DFSClient.SIZE_OF_INTEGER; // TODO(todd) strange
+      int packetSize = PacketHeader.PKT_HEADER_LEN + FSConstants.BYTES_IN_INTEGER;
       buf = new byte[packetSize];
       
       checksumStart = dataStart = packetSize;
@@ -235,12 +236,12 @@ class DFSOutputStream extends FSOutputSummer implements Syncable {
                          dataStart - checksumLen , checksumLen); 
       }
       
-      int pktLen = DFSClient.SIZE_OF_INTEGER + dataLen + checksumLen;
+      int pktLen = FSConstants.BYTES_IN_INTEGER + dataLen + checksumLen;
       
       //normally dataStart == checksumPos, i.e., offset is zero.
       buffer = ByteBuffer.wrap(
         buf, dataStart - checksumPos,
-        PacketHeader.PKT_HEADER_LEN + pktLen - DFSClient.SIZE_OF_INTEGER);
+        PacketHeader.PKT_HEADER_LEN + pktLen - FSConstants.BYTES_IN_INTEGER);
       buf = null;
       buffer.mark();
 
@@ -839,7 +840,7 @@ class DFSOutputStream extends FSOutputSummer implements Syncable {
         final long writeTimeout = dfsClient.getDatanodeWriteTimeout(2);
         out = new DataOutputStream(new BufferedOutputStream(
             NetUtils.getOutputStream(sock, writeTimeout),
-            DataNode.SMALL_BUFFER_SIZE));
+            FSConstants.SMALL_BUFFER_SIZE));
 
         //send the TRANSFER_BLOCK request
         new Sender(out).transferBlock(block, blockToken, dfsClient.clientName,
@@ -1011,7 +1012,7 @@ class DFSOutputStream extends FSOutputSummer implements Syncable {
         //
         DataOutputStream out = new DataOutputStream(new BufferedOutputStream(
             NetUtils.getOutputStream(s, writeTimeout),
-            DataNode.SMALL_BUFFER_SIZE));
+            FSConstants.SMALL_BUFFER_SIZE));
         blockReplyStream = new DataInputStream(NetUtils.getInputStream(s));
 
         // send the request
@@ -1156,7 +1157,7 @@ class DFSOutputStream extends FSOutputSummer implements Syncable {
     final int timeout = client.getDatanodeReadTimeout(length);
     NetUtils.connect(sock, isa, timeout);
     sock.setSoTimeout(timeout);
-    sock.setSendBufferSize(DFSClient.DEFAULT_DATA_SOCKET_SIZE);
+    sock.setSendBufferSize(FSConstants.DEFAULT_DATA_SOCKET_SIZE);
     if(DFSClient.LOG.isDebugEnabled()) {
       DFSClient.LOG.debug("Send buf size " + sock.getSendBufferSize());
     }

hdfs/src/java/org/apache/hadoop/hdfs/protocol/FSConstants.java

@@ -18,68 +18,71 @@
 package org.apache.hadoop.hdfs.protocol;
 
 import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 
 /************************************
  * Some handy constants
- *
+ * 
  ************************************/
 @InterfaceAudience.Private
-public interface FSConstants {
+public final class FSConstants {
+  /* Hidden constructor */
+  private FSConstants() {
+  }
+
   public static int MIN_BLOCKS_FOR_WRITE = 5;
 
   // Long that indicates "leave current quota unchanged"
   public static final long QUOTA_DONT_SET = Long.MAX_VALUE;
   public static final long QUOTA_RESET = -1L;
-  
+
   //
   // Timeouts, constants
   //
-  public static long HEARTBEAT_INTERVAL = 3;
-  public static long BLOCKREPORT_INTERVAL = 60 * 60 * 1000;
-  public static long BLOCKREPORT_INITIAL_DELAY = 0;
   public static final long LEASE_SOFTLIMIT_PERIOD = 60 * 1000;
   public static final long LEASE_HARDLIMIT_PERIOD = 60 * LEASE_SOFTLIMIT_PERIOD;
-  public static final long LEASE_RECOVER_PERIOD = 10 * 1000; //in ms
-  
-  // We need to limit the length and depth of a path in the filesystem.  HADOOP-438
-  // Currently we set the maximum length to 8k characters and the maximum depth to 1k.  
+  public static final long LEASE_RECOVER_PERIOD = 10 * 1000; // in ms
+
+  // We need to limit the length and depth of a path in the filesystem.
+  // HADOOP-438
+  // Currently we set the maximum length to 8k characters and the maximum depth
+  // to 1k.
   public static int MAX_PATH_LENGTH = 8000;
   public static int MAX_PATH_DEPTH = 1000;
-    
-  public static final int BUFFER_SIZE = new HdfsConfiguration().getInt("io.file.buffer.size", 4096);
-  //Used for writing header etc.
-  public static final int SMALL_BUFFER_SIZE = Math.min(BUFFER_SIZE/2, 512);
-  //TODO mb@media-style.com: should be conf injected?
-  public static final long DEFAULT_BLOCK_SIZE = 64 * 1024 * 1024;
-  public static final int DEFAULT_BYTES_PER_CHECKSUM = 512;
-  public static final int DEFAULT_WRITE_PACKET_SIZE = 64 * 1024;
-  public static final short DEFAULT_REPLICATION_FACTOR = 3;
-  public static final int DEFAULT_FILE_BUFFER_SIZE = 4096;
+
+  // TODO mb@media-style.com: should be conf injected?
   public static final int DEFAULT_DATA_SOCKET_SIZE = 128 * 1024;
+  public static final int IO_FILE_BUFFER_SIZE = new HdfsConfiguration().getInt(
+      DFSConfigKeys.IO_FILE_BUFFER_SIZE_KEY,
+      DFSConfigKeys.IO_FILE_BUFFER_SIZE_DEFAULT);
+  // Used for writing header etc.
+  public static final int SMALL_BUFFER_SIZE = Math.min(IO_FILE_BUFFER_SIZE / 2,
+      512);
 
-  public static final int SIZE_OF_INTEGER = Integer.SIZE / Byte.SIZE;
+  public static final int BYTES_IN_INTEGER = Integer.SIZE / Byte.SIZE;
 
   // SafeMode actions
-  public enum SafeModeAction{ SAFEMODE_LEAVE, SAFEMODE_ENTER, SAFEMODE_GET; }
+  public enum SafeModeAction {
+    SAFEMODE_LEAVE, SAFEMODE_ENTER, SAFEMODE_GET;
+  }
 
   // type of the datanode report
-  public static enum DatanodeReportType {ALL, LIVE, DEAD }
-  
+  public static enum DatanodeReportType {
+    ALL, LIVE, DEAD
+  }
+
   // An invalid transaction ID that will never be seen in a real namesystem.
   public static final long INVALID_TXID = -12345;
 
   /**
    * Distributed upgrade actions:
    * 
-   * 1. Get upgrade status.
-   * 2. Get detailed upgrade status.
-   * 3. Proceed with the upgrade if it is stuck, no matter what the status is.
+   * 1. Get upgrade status. 2. Get detailed upgrade status. 3. Proceed with the
+   * upgrade if it is stuck, no matter what the status is.
    */
   public static enum UpgradeAction {
-    GET_STATUS,
-    DETAILED_STATUS,
-    FORCE_PROCEED;
+    GET_STATUS, DETAILED_STATUS, FORCE_PROCEED;
   }
 
   /**
@@ -90,6 +93,6 @@ public interface FSConstants {
   /**
    * Please see {@link LayoutVersion} on adding new layout version.
    */
-  public static final int LAYOUT_VERSION = 
-    LayoutVersion.getCurrentLayoutVersion();
+  public static final int LAYOUT_VERSION = LayoutVersion
+      .getCurrentLayoutVersion();
 }

hdfs/src/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java

@@ -309,10 +309,10 @@ public class Balancer {
             target.datanode.getName()), HdfsConstants.READ_TIMEOUT);
         sock.setKeepAlive(true);
         out = new DataOutputStream( new BufferedOutputStream(
-            sock.getOutputStream(), FSConstants.BUFFER_SIZE));
+            sock.getOutputStream(), FSConstants.IO_FILE_BUFFER_SIZE));
         sendRequest(out);
         in = new DataInputStream( new BufferedInputStream(
-            sock.getInputStream(), FSConstants.BUFFER_SIZE));
+            sock.getInputStream(), FSConstants.IO_FILE_BUFFER_SIZE));
         receiveResponse(in);
         bytesMoved.inc(block.getNumBytes());
         LOG.info( "Moving block " + block.getBlock().getBlockId() +

hdfs/src/java/org/apache/hadoop/hdfs/server/common/HdfsConstants.java

@@ -29,7 +29,10 @@ import org.apache.hadoop.classification.InterfaceAudience;
  ************************************/
 
 @InterfaceAudience.Private
-public interface HdfsConstants {
+public final class HdfsConstants {
+  /* Hidden constructor */
+  private HdfsConstants() { }
+  
   /**
    * Type of the node
    */

hdfs/src/java/org/apache/hadoop/hdfs/server/common/JspHelper.java

@@ -190,13 +190,15 @@ public class JspHelper {
     s.connect(addr, HdfsConstants.READ_TIMEOUT);
     s.setSoTimeout(HdfsConstants.READ_TIMEOUT);
       
-      long amtToRead = Math.min(chunkSizeToView, blockSize - offsetIntoBlock);     
+    long amtToRead = Math.min(chunkSizeToView, blockSize - offsetIntoBlock);
       
       // Use the block name for file name. 
-      String file = BlockReader.getFileName(addr, poolId, blockId);
-      BlockReader blockReader = BlockReader.newBlockReader(s, file,
+    int bufferSize = conf.getInt(DFSConfigKeys.IO_FILE_BUFFER_SIZE_KEY,
+        DFSConfigKeys.IO_FILE_BUFFER_SIZE_DEFAULT);
+    String file = BlockReader.getFileName(addr, poolId, blockId);
+    BlockReader blockReader = BlockReader.newBlockReader(s, file,
         new ExtendedBlock(poolId, blockId, 0, genStamp), blockToken,
-        offsetIntoBlock, amtToRead, conf.getInt("io.file.buffer.size", 4096));
+        offsetIntoBlock, amtToRead, bufferSize);
         
     byte[] buf = new byte[(int)amtToRead];
     int readOffset = 0;

hdfs/src/java/org/apache/hadoop/hdfs/server/datanode/BlockReceiver.java

@@ -54,7 +54,7 @@ import org.apache.hadoop.util.PureJavaCrc32;
  * may copies it to another site. If a throttler is provided,
  * streaming throttling is also supported.
  **/
-class BlockReceiver implements Closeable, FSConstants {
+class BlockReceiver implements Closeable {
   public static final Log LOG = DataNode.LOG;
   static final Log ClientTraceLog = DataNode.ClientTraceLog;
   
@@ -179,8 +179,7 @@ class BlockReceiver implements Closeable, FSConstants {
         this.out = streams.dataOut;
         this.cout = streams.checksumOut;
         this.checksumOut = new DataOutputStream(new BufferedOutputStream(
-                                                  streams.checksumOut,
-                                                  SMALL_BUFFER_SIZE));
+            streams.checksumOut, FSConstants.SMALL_BUFFER_SIZE));
         // write data chunk header if creating a new replica
         if (isCreate) {
           BlockMetadataHeader.writeHeader(checksumOut, checksum);
@@ -399,7 +398,7 @@ class BlockReceiver implements Closeable, FSConstants {
       buf.limit(bufRead);
     }
     
-    while (buf.remaining() < SIZE_OF_INTEGER) {
+    while (buf.remaining() < FSConstants.BYTES_IN_INTEGER) {
       if (buf.position() > 0) {
         shiftBufData();
       }
@@ -418,9 +417,10 @@ class BlockReceiver implements Closeable, FSConstants {
                             payloadLen);
     }
     
-    // Subtract SIZE_OF_INTEGER since that accounts for the payloadLen that
+    // Subtract BYTES_IN_INTEGER since that accounts for the payloadLen that
     // we read above.
-    int pktSize = payloadLen + PacketHeader.PKT_HEADER_LEN - SIZE_OF_INTEGER;
+    int pktSize = payloadLen + PacketHeader.PKT_HEADER_LEN
+        - FSConstants.BYTES_IN_INTEGER;
     
     if (buf.remaining() < pktSize) {
       //we need to read more data
@@ -817,7 +817,7 @@ class BlockReceiver implements Closeable, FSConstants {
    * Processed responses from downstream datanodes in the pipeline
    * and sends back replies to the originator.
    */
-  class PacketResponder implements Runnable, Closeable, FSConstants {   
+  class PacketResponder implements Runnable, Closeable {   
 
     /** queue for packets waiting for ack */
     private final LinkedList<Packet> ackQueue = new LinkedList<Packet>(); 

hdfs/src/java/org/apache/hadoop/hdfs/server/datanode/BlockSender.java

@@ -42,7 +42,7 @@ import org.apache.hadoop.util.DataChecksum;
 /**
  * Reads a block from the disk and sends it to a recipient.
  */
-class BlockSender implements java.io.Closeable, FSConstants {
+class BlockSender implements java.io.Closeable {
   public static final Log LOG = DataNode.LOG;
   static final Log ClientTraceLog = DataNode.ClientTraceLog;
   
@@ -155,7 +155,7 @@ class BlockSender implements java.io.Closeable, FSConstants {
 
       if ( !corruptChecksumOk || datanode.data.metaFileExists(block) ) {
         checksumIn = new DataInputStream(new BufferedInputStream(datanode.data
-            .getMetaDataInputStream(block), BUFFER_SIZE));
+            .getMetaDataInputStream(block), FSConstants.IO_FILE_BUFFER_SIZE));
 
         // read and handle the common header here. For now just a version
        BlockMetadataHeader header = BlockMetadataHeader.readHeader(checksumIn);
@@ -472,15 +472,15 @@ class BlockSender implements java.io.Closeable, FSConstants {
         streamForSendChunks = baseStream;
         
         // assure a mininum buffer size.
-        maxChunksPerPacket = (Math.max(BUFFER_SIZE, 
+        maxChunksPerPacket = (Math.max(FSConstants.IO_FILE_BUFFER_SIZE, 
                                        MIN_BUFFER_WITH_TRANSFERTO)
                               + bytesPerChecksum - 1)/bytesPerChecksum;
         
         // allocate smaller buffer while using transferTo(). 
         pktSize += checksumSize * maxChunksPerPacket;
       } else {
-        maxChunksPerPacket = Math.max(1,
-                 (BUFFER_SIZE + bytesPerChecksum - 1)/bytesPerChecksum);
+        maxChunksPerPacket = Math.max(1, (FSConstants.IO_FILE_BUFFER_SIZE
+            + bytesPerChecksum - 1) / bytesPerChecksum);
         pktSize += (bytesPerChecksum + checksumSize) * maxChunksPerPacket;
       }
 

hdfs/src/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -169,7 +169,7 @@ import org.mortbay.util.ajax.JSON;
  **********************************************************/
 @InterfaceAudience.Private
 public class DataNode extends Configured 
-    implements InterDatanodeProtocol, ClientDatanodeProtocol, FSConstants,
+    implements InterDatanodeProtocol, ClientDatanodeProtocol,
     DataNodeMXBean {
   public static final Log LOG = LogFactory.getLog(DataNode.class);
   
@@ -348,7 +348,7 @@ public class DataNode extends Configured
   ThreadGroup threadGroup = null;
   long blockReportInterval;
   boolean resetBlockReportTime = true;
-  long initialBlockReportDelay = BLOCKREPORT_INITIAL_DELAY * 1000L;
+  long initialBlockReportDelay = DFS_BLOCKREPORT_INTERVAL_MSEC_DEFAULT * 1000L;
   long heartBeatInterval;
   private boolean heartbeatsDisabledForTests = false;
   private DataStorage storage = null;
@@ -440,21 +440,23 @@ public class DataNode extends Configured
                                           HdfsConstants.WRITE_TIMEOUT);
     /* Based on results on different platforms, we might need set the default 
      * to false on some of them. */
-    this.transferToAllowed = conf.getBoolean("dfs.datanode.transferTo.allowed", 
-                                             true);
+    this.transferToAllowed = conf.getBoolean(
+        DFS_DATANODE_TRANSFERTO_ALLOWED_KEY,
+        DFS_DATANODE_TRANSFERTO_ALLOWED_DEFAULT);
     this.writePacketSize = conf.getInt(DFS_CLIENT_WRITE_PACKET_SIZE_KEY, 
                                        DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT);
-
-    this.blockReportInterval =
-      conf.getLong(DFS_BLOCKREPORT_INTERVAL_MSEC_KEY, BLOCKREPORT_INTERVAL);
-    this.initialBlockReportDelay = conf.getLong(DFS_BLOCKREPORT_INITIAL_DELAY_KEY,
-                                            BLOCKREPORT_INITIAL_DELAY)* 1000L; 
+    this.blockReportInterval = conf.getLong(DFS_BLOCKREPORT_INTERVAL_MSEC_KEY,
+        DFS_BLOCKREPORT_INTERVAL_MSEC_DEFAULT);
+    this.initialBlockReportDelay = conf.getLong(
+        DFS_BLOCKREPORT_INITIAL_DELAY_KEY,
+        DFS_BLOCKREPORT_INITIAL_DELAY_DEFAULT) * 1000L;
     if (this.initialBlockReportDelay >= blockReportInterval) {
       this.initialBlockReportDelay = 0;
       LOG.info("dfs.blockreport.initialDelay is greater than " +
         "dfs.blockreport.intervalMsec." + " Setting initial delay to 0 msec:");
     }
-    this.heartBeatInterval = conf.getLong(DFS_HEARTBEAT_INTERVAL_KEY, HEARTBEAT_INTERVAL) * 1000L;
+    this.heartBeatInterval = conf.getLong(DFS_HEARTBEAT_INTERVAL_KEY,
+        DFS_HEARTBEAT_INTERVAL_DEFAULT) * 1000L;
 
     // do we need to sync block file contents to disk when blockfile is closed?
     this.syncOnClose = conf.getBoolean(DFS_DATANODE_SYNCONCLOSE_KEY, 
@@ -617,7 +619,7 @@ public class DataNode extends Configured
     } else {
       ss = secureResources.getStreamingSocket();
     }
-    ss.setReceiveBufferSize(DEFAULT_DATA_SOCKET_SIZE); 
+    ss.setReceiveBufferSize(FSConstants.DEFAULT_DATA_SOCKET_SIZE); 
     // adjust machine name with the actual port
     int tmpPort = ss.getLocalPort();
     selfAddr = new InetSocketAddress(ss.getInetAddress().getHostAddress(),
@@ -1967,8 +1969,8 @@ public class DataNode extends Configured
         long writeTimeout = socketWriteTimeout + 
                             HdfsConstants.WRITE_TIMEOUT_EXTENSION * (targets.length-1);
         OutputStream baseStream = NetUtils.getOutputStream(sock, writeTimeout);
-        out = new DataOutputStream(new BufferedOutputStream(baseStream, 
-                                                            SMALL_BUFFER_SIZE));
+        out = new DataOutputStream(new BufferedOutputStream(baseStream,
+            FSConstants.SMALL_BUFFER_SIZE));
         blockSender = new BlockSender(b, 0, b.getNumBytes(), 
             false, false, false, DataNode.this);
         DatanodeInfo srcNode = new DatanodeInfo(bpReg);

hdfs/src/java/org/apache/hadoop/hdfs/server/datanode/DataXceiver.java

@@ -69,7 +69,7 @@ import com.google.protobuf.ByteString;
 /**
  * Thread for processing incoming/outgoing data stream.
  */
-class DataXceiver extends Receiver implements Runnable, FSConstants {
+class DataXceiver extends Receiver implements Runnable {
   public static final Log LOG = DataNode.LOG;
   static final Log ClientTraceLog = DataNode.ClientTraceLog;
   
@@ -202,8 +202,8 @@ class DataXceiver extends Receiver implements Runnable, FSConstants {
       final long length) throws IOException {
     OutputStream baseStream = NetUtils.getOutputStream(s, 
         datanode.socketWriteTimeout);
-    DataOutputStream out = new DataOutputStream(
-                 new BufferedOutputStream(baseStream, SMALL_BUFFER_SIZE));
+    DataOutputStream out = new DataOutputStream(new BufferedOutputStream(
+        baseStream, FSConstants.SMALL_BUFFER_SIZE));
     checkAccess(out, true, block, blockToken,
         Op.READ_BLOCK, BlockTokenSecretManager.AccessMode.READ);
   
@@ -329,7 +329,7 @@ class DataXceiver extends Receiver implements Runnable, FSConstants {
     final DataOutputStream replyOut = new DataOutputStream(
         new BufferedOutputStream(
             NetUtils.getOutputStream(s, datanode.socketWriteTimeout),
-            SMALL_BUFFER_SIZE));
+            FSConstants.SMALL_BUFFER_SIZE));
     checkAccess(replyOut, isClient, block, blockToken,
         Op.WRITE_BLOCK, BlockTokenSecretManager.AccessMode.WRITE);
 
@@ -369,11 +369,11 @@ class DataXceiver extends Receiver implements Runnable, FSConstants {
                       (HdfsConstants.WRITE_TIMEOUT_EXTENSION * targets.length);
           NetUtils.connect(mirrorSock, mirrorTarget, timeoutValue);
           mirrorSock.setSoTimeout(timeoutValue);
-          mirrorSock.setSendBufferSize(DEFAULT_DATA_SOCKET_SIZE);
+          mirrorSock.setSendBufferSize(FSConstants.DEFAULT_DATA_SOCKET_SIZE);
           mirrorOut = new DataOutputStream(
              new BufferedOutputStream(
                          NetUtils.getOutputStream(mirrorSock, writeTimeout),
-                         SMALL_BUFFER_SIZE));
+                         FSConstants.SMALL_BUFFER_SIZE));
           mirrorIn = new DataInputStream(NetUtils.getInputStream(mirrorSock));
 
           new Sender(mirrorOut).writeBlock(originalBlock, blockToken,
@@ -524,7 +524,7 @@ class DataXceiver extends Receiver implements Runnable, FSConstants {
     final MetaDataInputStream metadataIn = 
       datanode.data.getMetaDataInputStream(block);
     final DataInputStream checksumIn = new DataInputStream(new BufferedInputStream(
-        metadataIn, BUFFER_SIZE));
+        metadataIn, FSConstants.IO_FILE_BUFFER_SIZE));
 
     updateCurrentThreadName("Getting checksum for block " + block);
     try {
@@ -603,7 +603,7 @@ class DataXceiver extends Receiver implements Runnable, FSConstants {
       OutputStream baseStream = NetUtils.getOutputStream(
           s, datanode.socketWriteTimeout);
       reply = new DataOutputStream(new BufferedOutputStream(
-          baseStream, SMALL_BUFFER_SIZE));
+          baseStream, FSConstants.SMALL_BUFFER_SIZE));
 
       // send status first
       writeResponse(SUCCESS, reply);
@@ -681,15 +681,15 @@ class DataXceiver extends Receiver implements Runnable, FSConstants {
 
       OutputStream baseStream = NetUtils.getOutputStream(proxySock, 
           datanode.socketWriteTimeout);
-      proxyOut = new DataOutputStream(
-                     new BufferedOutputStream(baseStream, SMALL_BUFFER_SIZE));
+      proxyOut = new DataOutputStream(new BufferedOutputStream(baseStream,
+          FSConstants.SMALL_BUFFER_SIZE));
 
       /* send request to the proxy */
       new Sender(proxyOut).copyBlock(block, blockToken);
 
       // receive the response from the proxy
       proxyReply = new DataInputStream(new BufferedInputStream(
-          NetUtils.getInputStream(proxySock), BUFFER_SIZE));
+          NetUtils.getInputStream(proxySock), FSConstants.IO_FILE_BUFFER_SIZE));
       BlockOpResponseProto copyResponse = BlockOpResponseProto.parseFrom(
           HdfsProtoUtil.vintPrefixed(proxyReply));
 

hdfs/src/java/org/apache/hadoop/hdfs/server/datanode/DataXceiverServer.java

@@ -42,7 +42,7 @@ import org.apache.hadoop.util.Daemon;
  * other DataNodes.  This small server does not use the 
  * Hadoop IPC mechanism.
  */
-class DataXceiverServer implements Runnable, FSConstants {
+class DataXceiverServer implements Runnable {
   public static final Log LOG = DataNode.LOG;
   
   ServerSocket ss;
@@ -119,8 +119,8 @@ class DataXceiverServer implements Runnable, FSConstants {
       conf.getInt(DFSConfigKeys.DFS_DATANODE_MAX_RECEIVER_THREADS_KEY,
                   DFSConfigKeys.DFS_DATANODE_MAX_RECEIVER_THREADS_DEFAULT);
     
-    this.estimateBlockSize = 
-      conf.getLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, DEFAULT_BLOCK_SIZE);
+    this.estimateBlockSize = conf.getLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY,
+        DFSConfigKeys.DFS_BLOCK_SIZE_DEFAULT);
     
     //set up parameter for cluster balancing
     this.balanceThrottler = new BlockBalanceThrottler(

hdfs/src/java/org/apache/hadoop/hdfs/server/datanode/FSDataset.java

@@ -75,7 +75,7 @@ import org.apache.hadoop.util.ReflectionUtils;
  *
  ***************************************************/
 @InterfaceAudience.Private
-public class FSDataset implements FSConstants, FSDatasetInterface {
+public class FSDataset implements FSDatasetInterface {
 
   /**
    * A node type that can be built into a tree reflecting the
@@ -465,7 +465,7 @@ public class FSDataset implements FSConstants, FSDatasetInterface {
         }
         checksumIn = new DataInputStream(
             new BufferedInputStream(new FileInputStream(metaFile),
-                BUFFER_SIZE));
+                FSConstants.IO_FILE_BUFFER_SIZE));
 
         // read and handle the common header here. For now just a version
         BlockMetadataHeader header = BlockMetadataHeader.readHeader(checksumIn);

hdfs/src/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -67,7 +67,7 @@ import org.apache.hadoop.fs.UnresolvedLinkException;
 import org.apache.hadoop.fs.permission.FsAction;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.fs.permission.PermissionStatus;
-import org.apache.hadoop.hdfs.DFSConfigKeys;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.*;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException;
@@ -78,6 +78,9 @@ import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.DirectoryListing;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.FSConstants;
+import org.apache.hadoop.hdfs.protocol.FSConstants.DatanodeReportType;
+import org.apache.hadoop.hdfs.protocol.FSConstants.SafeModeAction;
+import org.apache.hadoop.hdfs.protocol.FSConstants.UpgradeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
@@ -146,7 +149,7 @@ import org.mortbay.util.ajax.JSON;
  ***************************************************/
 @InterfaceAudience.Private
 @Metrics(context="dfs")
-public class FSNamesystem implements RwLock, FSConstants, FSClusterStats,
+public class FSNamesystem implements RwLock, FSClusterStats,
     FSNamesystemMBean, NameNodeMXBean {
   static final Log LOG = LogFactory.getLog(FSNamesystem.class);
 
@@ -274,9 +277,9 @@ public class FSNamesystem implements RwLock, FSConstants, FSClusterStats,
    */
   private void initialize(Configuration conf, FSImage fsImage)
       throws IOException {
-    resourceRecheckInterval =
-        conf.getLong(DFSConfigKeys.DFS_NAMENODE_RESOURCE_CHECK_INTERVAL_KEY,
-        DFSConfigKeys.DFS_NAMENODE_RESOURCE_CHECK_INTERVAL_DEFAULT);
+    resourceRecheckInterval = conf.getLong(
+        DFS_NAMENODE_RESOURCE_CHECK_INTERVAL_KEY,
+        DFS_NAMENODE_RESOURCE_CHECK_INTERVAL_DEFAULT);
     nnResourceChecker = new NameNodeResourceChecker(conf);
     checkAvailableResources();
     this.systemStart = now();
@@ -323,7 +326,7 @@ public class FSNamesystem implements RwLock, FSConstants, FSClusterStats,
   }
 
   public static Collection<URI> getNamespaceDirs(Configuration conf) {
-    return getStorageDirs(conf, DFSConfigKeys.DFS_NAMENODE_NAME_DIR_KEY);
+    return getStorageDirs(conf, DFS_NAMENODE_NAME_DIR_KEY);
   }
 
   private static Collection<URI> getStorageDirs(Configuration conf,
@@ -357,7 +360,7 @@ public class FSNamesystem implements RwLock, FSConstants, FSClusterStats,
   }
 
   public static Collection<URI> getNamespaceEditsDirs(Configuration conf) {
-    return getStorageDirs(conf, DFSConfigKeys.DFS_NAMENODE_EDITS_DIR_KEY);
+    return getStorageDirs(conf, DFS_NAMENODE_EDITS_DIR_KEY);
   }
 
   @Override
@@ -429,29 +432,30 @@ public class FSNamesystem implements RwLock, FSConstants, FSClusterStats,
     
     LOG.info("fsOwner=" + fsOwner);
 
-    this.supergroup = conf.get(DFSConfigKeys.DFS_PERMISSIONS_SUPERUSERGROUP_KEY, 
-                               DFSConfigKeys.DFS_PERMISSIONS_SUPERUSERGROUP_DEFAULT);
-    this.isPermissionEnabled = conf.getBoolean(DFSConfigKeys.DFS_PERMISSIONS_ENABLED_KEY,
-                                               DFSConfigKeys.DFS_PERMISSIONS_ENABLED_DEFAULT);
+    this.supergroup = conf.get(DFS_PERMISSIONS_SUPERUSERGROUP_KEY, 
+                               DFS_PERMISSIONS_SUPERUSERGROUP_DEFAULT);
+    this.isPermissionEnabled = conf.getBoolean(DFS_PERMISSIONS_ENABLED_KEY,
+                                               DFS_PERMISSIONS_ENABLED_DEFAULT);
     LOG.info("supergroup=" + supergroup);
     LOG.info("isPermissionEnabled=" + isPermissionEnabled);
-    short filePermission = (short)conf.getInt(DFSConfigKeys.DFS_NAMENODE_UPGRADE_PERMISSION_KEY,
-                                              DFSConfigKeys.DFS_NAMENODE_UPGRADE_PERMISSION_DEFAULT);
+    short filePermission = (short)conf.getInt(DFS_NAMENODE_UPGRADE_PERMISSION_KEY,
+                                              DFS_NAMENODE_UPGRADE_PERMISSION_DEFAULT);
     this.defaultPermission = PermissionStatus.createImmutable(
         fsOwner.getShortUserName(), supergroup, new FsPermission(filePermission));
     
     this.serverDefaults = new FsServerDefaults(
-        conf.getLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, DEFAULT_BLOCK_SIZE),
-        conf.getInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, DEFAULT_BYTES_PER_CHECKSUM),
-        conf.getInt(DFSConfigKeys.DFS_CLIENT_WRITE_PACKET_SIZE_KEY, DEFAULT_WRITE_PACKET_SIZE),
-        (short) conf.getInt(DFSConfigKeys.DFS_REPLICATION_KEY, DEFAULT_REPLICATION_FACTOR),
-        conf.getInt("io.file.buffer.size", DEFAULT_FILE_BUFFER_SIZE));
-    this.maxFsObjects = conf.getLong(DFSConfigKeys.DFS_NAMENODE_MAX_OBJECTS_KEY, 
-                                     DFSConfigKeys.DFS_NAMENODE_MAX_OBJECTS_DEFAULT);
-
-    this.accessTimePrecision = conf.getLong(DFSConfigKeys.DFS_NAMENODE_ACCESSTIME_PRECISION_KEY, 0);
-    this.supportAppends = conf.getBoolean(DFSConfigKeys.DFS_SUPPORT_APPEND_KEY,
-                                      DFSConfigKeys.DFS_SUPPORT_APPEND_DEFAULT);
+        conf.getLong(DFS_BLOCK_SIZE_KEY, DFS_BLOCK_SIZE_DEFAULT),
+        conf.getInt(DFS_BYTES_PER_CHECKSUM_KEY, DFS_BYTES_PER_CHECKSUM_DEFAULT),
+        conf.getInt(DFS_CLIENT_WRITE_PACKET_SIZE_KEY, DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT),
+        (short) conf.getInt(DFS_REPLICATION_KEY, DFS_REPLICATION_DEFAULT),
+        conf.getInt(IO_FILE_BUFFER_SIZE_KEY, IO_FILE_BUFFER_SIZE_DEFAULT));
+    
+    this.maxFsObjects = conf.getLong(DFS_NAMENODE_MAX_OBJECTS_KEY, 
+                                     DFS_NAMENODE_MAX_OBJECTS_DEFAULT);
+
+    this.accessTimePrecision = conf.getLong(DFS_NAMENODE_ACCESSTIME_PRECISION_KEY, 0);
+    this.supportAppends = conf.getBoolean(DFS_SUPPORT_APPEND_KEY,
+        DFS_SUPPORT_APPEND_DEFAULT);
 
     this.dtpReplaceDatanodeOnFailure = ReplaceDatanodeOnFailure.get(conf);
   }
@@ -2798,16 +2802,17 @@ public class FSNamesystem implements RwLock, FSConstants, FSClusterStats,
      * @param conf configuration
      */
     SafeModeInfo(Configuration conf) {
-      this.threshold = conf.getFloat(DFSConfigKeys.DFS_NAMENODE_SAFEMODE_THRESHOLD_PCT_KEY, DFSConfigKeys.DFS_NAMENODE_SAFEMODE_THRESHOLD_PCT_DEFAULT);
+      this.threshold = conf.getFloat(DFS_NAMENODE_SAFEMODE_THRESHOLD_PCT_KEY,
+          DFS_NAMENODE_SAFEMODE_THRESHOLD_PCT_DEFAULT);
       this.datanodeThreshold = conf.getInt(
-        DFSConfigKeys.DFS_NAMENODE_SAFEMODE_MIN_DATANODES_KEY,
-        DFSConfigKeys.DFS_NAMENODE_SAFEMODE_MIN_DATANODES_DEFAULT);
-      this.extension = conf.getInt(DFSConfigKeys.DFS_NAMENODE_SAFEMODE_EXTENSION_KEY, 0);
-      this.safeReplication = conf.getInt(DFSConfigKeys.DFS_NAMENODE_REPLICATION_MIN_KEY, 
-                                         DFSConfigKeys.DFS_NAMENODE_REPLICATION_MIN_DEFAULT);
+        DFS_NAMENODE_SAFEMODE_MIN_DATANODES_KEY,
+        DFS_NAMENODE_SAFEMODE_MIN_DATANODES_DEFAULT);
+      this.extension = conf.getInt(DFS_NAMENODE_SAFEMODE_EXTENSION_KEY, 0);
+      this.safeReplication = conf.getInt(DFS_NAMENODE_REPLICATION_MIN_KEY, 
+                                         DFS_NAMENODE_REPLICATION_MIN_DEFAULT);
       // default to safe mode threshold (i.e., don't populate queues before leaving safe mode)
       this.replQueueThreshold = 
-        conf.getFloat(DFSConfigKeys.DFS_NAMENODE_REPL_QUEUE_THRESHOLD_PCT_KEY,
+        conf.getFloat(DFS_NAMENODE_REPL_QUEUE_THRESHOLD_PCT_KEY,
                       (float) threshold);
       this.blockTotal = 0; 
       this.blockSafe = 0;
@@ -3977,14 +3982,12 @@ public class FSNamesystem implements RwLock, FSConstants, FSClusterStats,
   private DelegationTokenSecretManager createDelegationTokenSecretManager(
       Configuration conf) {
     return new DelegationTokenSecretManager(conf.getLong(
-        DFSConfigKeys.DFS_NAMENODE_DELEGATION_KEY_UPDATE_INTERVAL_KEY,
-        DFSConfigKeys.DFS_NAMENODE_DELEGATION_KEY_UPDATE_INTERVAL_DEFAULT),
-        conf.getLong(
-            DFSConfigKeys.DFS_NAMENODE_DELEGATION_TOKEN_MAX_LIFETIME_KEY,
-            DFSConfigKeys.DFS_NAMENODE_DELEGATION_TOKEN_MAX_LIFETIME_DEFAULT),
-        conf.getLong(
-            DFSConfigKeys.DFS_NAMENODE_DELEGATION_TOKEN_RENEW_INTERVAL_KEY,
-            DFSConfigKeys.DFS_NAMENODE_DELEGATION_TOKEN_RENEW_INTERVAL_DEFAULT),
+        DFS_NAMENODE_DELEGATION_KEY_UPDATE_INTERVAL_KEY,
+        DFS_NAMENODE_DELEGATION_KEY_UPDATE_INTERVAL_DEFAULT),
+        conf.getLong(DFS_NAMENODE_DELEGATION_TOKEN_MAX_LIFETIME_KEY,
+            DFS_NAMENODE_DELEGATION_TOKEN_MAX_LIFETIME_DEFAULT),
+        conf.getLong(DFS_NAMENODE_DELEGATION_TOKEN_RENEW_INTERVAL_KEY,
+            DFS_NAMENODE_DELEGATION_TOKEN_RENEW_INTERVAL_DEFAULT),
         DELEGATION_TOKEN_REMOVER_SCAN_INTERVAL, this);
   }
 

hdfs/src/java/org/apache/hadoop/hdfs/server/namenode/NameNode.java

@@ -56,6 +56,11 @@ import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.DirectoryListing;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.FSConstants;
+import org.apache.hadoop.hdfs.protocol.FSConstants.DatanodeReportType;
+import org.apache.hadoop.hdfs.protocol.FSConstants.SafeModeAction;
+import org.apache.hadoop.hdfs.protocol.FSConstants.UpgradeAction;
+import static org.apache.hadoop.hdfs.protocol.FSConstants.MAX_PATH_LENGTH;
+import static org.apache.hadoop.hdfs.protocol.FSConstants.MAX_PATH_DEPTH;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
@@ -140,7 +145,7 @@ import org.apache.hadoop.util.StringUtils;
  * NameNode state, for example partial blocksMap etc.
  **********************************************************/
 @InterfaceAudience.Private
-public class NameNode implements NamenodeProtocols, FSConstants {
+public class NameNode implements NamenodeProtocols {
   static{
     HdfsConfiguration.init();
   }
@@ -718,8 +723,8 @@ public class NameNode implements NamenodeProtocols, FSConstants {
                          +src+" for "+clientName+" at "+clientMachine);
     }
     if (!checkPathLength(src)) {
-      throw new IOException("create: Pathname too long.  Limit " 
-                            + MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
+      throw new IOException("create: Pathname too long.  Limit "
+          + MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
     }
     namesystem.startFile(src,
         new PermissionStatus(UserGroupInformation.getCurrentUser().getShortUserName(),
@@ -896,8 +901,8 @@ public class NameNode implements NamenodeProtocols, FSConstants {
       stateChangeLog.debug("*DIR* NameNode.rename: " + src + " to " + dst);
     }
     if (!checkPathLength(dst)) {
-      throw new IOException("rename: Pathname too long.  Limit " 
-                            + MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
+      throw new IOException("rename: Pathname too long.  Limit "
+          + MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
     }
     boolean ret = namesystem.renameTo(src, dst);
     if (ret) {
@@ -918,8 +923,8 @@ public class NameNode implements NamenodeProtocols, FSConstants {
       stateChangeLog.debug("*DIR* NameNode.rename: " + src + " to " + dst);
     }
     if (!checkPathLength(dst)) {
-      throw new IOException("rename: Pathname too long.  Limit " 
-                            + MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
+      throw new IOException("rename: Pathname too long.  Limit "
+          + MAX_PATH_LENGTH + " characters, " + MAX_PATH_DEPTH + " levels.");
     }
     namesystem.renameTo(src, dst, options);
     metrics.incrFilesRenamed();
@@ -1274,7 +1279,7 @@ public class NameNode implements NamenodeProtocols, FSConstants {
    * @throws IOException
    */
   public void verifyVersion(int version) throws IOException {
-    if (version != LAYOUT_VERSION)
+    if (version != FSConstants.LAYOUT_VERSION)
       throw new IncorrectVersionException(version, "data node");
   }
     

hdfs/src/java/org/apache/hadoop/hdfs/server/namenode/TransferFsImage.java

@@ -41,7 +41,7 @@ import com.google.common.collect.Lists;
 /**
  * This class provides fetching a specified file from the NameNode.
  */
-class TransferFsImage implements FSConstants {
+class TransferFsImage {
   
   public final static String CONTENT_LENGTH = "Content-Length";
   public final static String MD5_HEADER = "X-MD5-Digest";
@@ -124,7 +124,7 @@ class TransferFsImage implements FSConstants {
   static void getFileServer(OutputStream outstream, File localfile,
       DataTransferThrottler throttler) 
     throws IOException {
-    byte buf[] = new byte[BUFFER_SIZE];
+    byte buf[] = new byte[FSConstants.IO_FILE_BUFFER_SIZE];
     FileInputStream infile = null;
     try {
       infile = new FileInputStream(localfile);
@@ -139,7 +139,7 @@ class TransferFsImage implements FSConstants {
           && localfile.getAbsolutePath().contains("fsimage")) {
           // Test sending image shorter than localfile
           long len = localfile.length();
-          buf = new byte[(int)Math.min(len/2, BUFFER_SIZE)];
+          buf = new byte[(int)Math.min(len/2, FSConstants.IO_FILE_BUFFER_SIZE)];
           // This will read at most half of the image
           // and the rest of the image will be sent over the wire
           infile.read(buf);
@@ -179,7 +179,7 @@ class TransferFsImage implements FSConstants {
   static MD5Hash getFileClient(String nnHostPort,
       String queryString, List<File> localPaths,
       NNStorage dstStorage, boolean getChecksum) throws IOException {
-    byte[] buf = new byte[BUFFER_SIZE];
+    byte[] buf = new byte[FSConstants.IO_FILE_BUFFER_SIZE];
     String proto = UserGroupInformation.isSecurityEnabled() ? "https://" : "http://";
     StringBuilder str = new StringBuilder(proto+nnHostPort+"/getimage?");
     str.append(queryString);

hdfs/src/test/hdfs/org/apache/hadoop/hdfs/DFSTestUtil.java

@@ -54,6 +54,7 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.DFSClient.DFSDataInputStream;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
+import org.apache.hadoop.hdfs.protocol.FSConstants;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
@@ -669,7 +670,7 @@ public class DFSTestUtil {
     final long writeTimeout = dfsClient.getDatanodeWriteTimeout(datanodes.length);
     final DataOutputStream out = new DataOutputStream(new BufferedOutputStream(
         NetUtils.getOutputStream(s, writeTimeout),
-        DataNode.SMALL_BUFFER_SIZE));
+        FSConstants.SMALL_BUFFER_SIZE));
     final DataInputStream in = new DataInputStream(NetUtils.getInputStream(s));
 
     // send the request

hdfs/src/test/hdfs/org/apache/hadoop/hdfs/TestDFSRemove.java

@@ -24,7 +24,6 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.protocol.FSConstants;
 import org.apache.hadoop.hdfs.server.datanode.DataNode;
 
 public class TestDFSRemove extends junit.framework.TestCase {
@@ -73,7 +72,7 @@ public class TestDFSRemove extends junit.framework.TestCase {
           fs.delete(a, false);
         }
         // wait 3 heartbeat intervals, so that all blocks are deleted.
-        Thread.sleep(3 * FSConstants.HEARTBEAT_INTERVAL * 1000);
+        Thread.sleep(3 * DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_DEFAULT * 1000);
         // all blocks should be gone now.
         long dfsUsedFinal = getTotalDfsUsed(cluster);
         assertEquals("All blocks should be gone. start=" + dfsUsedStart

hdfs/src/test/hdfs/org/apache/hadoop/hdfs/TestFileCreation.java

@@ -36,6 +36,7 @@ import org.apache.hadoop.fs.FsServerDefaults;
 import org.apache.hadoop.fs.ParentNotDirectoryException;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.permission.FsPermission;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.*;
 import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -100,23 +101,23 @@ public class TestFileCreation extends junit.framework.TestCase {
    */
   public void testServerDefaults() throws IOException {
     Configuration conf = new HdfsConfiguration();
-    conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, FSConstants.DEFAULT_BLOCK_SIZE);
-    conf.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, FSConstants.DEFAULT_BYTES_PER_CHECKSUM);
-    conf.setInt(DFSConfigKeys.DFS_CLIENT_WRITE_PACKET_SIZE_KEY, FSConstants.DEFAULT_WRITE_PACKET_SIZE);
-    conf.setInt(DFSConfigKeys.DFS_REPLICATION_KEY, FSConstants.DEFAULT_REPLICATION_FACTOR + 1);
-    conf.setInt("io.file.buffer.size", FSConstants.DEFAULT_FILE_BUFFER_SIZE);
+    conf.setLong(DFS_BLOCK_SIZE_KEY, DFS_BLOCK_SIZE_DEFAULT);
+    conf.setInt(DFS_BYTES_PER_CHECKSUM_KEY, DFS_BYTES_PER_CHECKSUM_DEFAULT);
+    conf.setInt(DFS_CLIENT_WRITE_PACKET_SIZE_KEY, DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT);
+    conf.setInt(DFS_REPLICATION_KEY, DFS_REPLICATION_DEFAULT + 1);
+    conf.setInt(IO_FILE_BUFFER_SIZE_KEY, IO_FILE_BUFFER_SIZE_DEFAULT);
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf)
-                     .numDataNodes(FSConstants.DEFAULT_REPLICATION_FACTOR + 1)
+                     .numDataNodes(DFSConfigKeys.DFS_REPLICATION_DEFAULT + 1)
                      .build();
     cluster.waitActive();
     FileSystem fs = cluster.getFileSystem();
     try {
       FsServerDefaults serverDefaults = fs.getServerDefaults();
-      assertEquals(FSConstants.DEFAULT_BLOCK_SIZE, serverDefaults.getBlockSize());
-      assertEquals(FSConstants.DEFAULT_BYTES_PER_CHECKSUM, serverDefaults.getBytesPerChecksum());
-      assertEquals(FSConstants.DEFAULT_WRITE_PACKET_SIZE, serverDefaults.getWritePacketSize());
-      assertEquals(FSConstants.DEFAULT_REPLICATION_FACTOR + 1, serverDefaults.getReplication());
-      assertEquals(FSConstants.DEFAULT_FILE_BUFFER_SIZE, serverDefaults.getFileBufferSize());
+      assertEquals(DFS_BLOCK_SIZE_DEFAULT, serverDefaults.getBlockSize());
+      assertEquals(DFS_BYTES_PER_CHECKSUM_DEFAULT, serverDefaults.getBytesPerChecksum());
+      assertEquals(DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT, serverDefaults.getWritePacketSize());
+      assertEquals(DFS_REPLICATION_DEFAULT + 1, serverDefaults.getReplication());
+      assertEquals(IO_FILE_BUFFER_SIZE_DEFAULT, serverDefaults.getFileBufferSize());
     } finally {
       fs.close();
       cluster.shutdown();
@@ -269,8 +270,8 @@ public class TestFileCreation extends junit.framework.TestCase {
    */
   public void testFileCreationError1() throws IOException {
     Configuration conf = new HdfsConfiguration();
-    conf.setInt(DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
-    conf.setInt(DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY, 1);
+    conf.setInt(DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
+    conf.setInt(DFS_HEARTBEAT_INTERVAL_KEY, 1);
     if (simulatedStorage) {
       conf.setBoolean(SimulatedFSDataset.CONFIG_PROPERTY_SIMULATED, true);
     }
@@ -343,8 +344,8 @@ public class TestFileCreation extends junit.framework.TestCase {
     long leasePeriod = 1000;
     System.out.println("testFileCreationError2 start");
     Configuration conf = new HdfsConfiguration();
-    conf.setInt(DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
-    conf.setInt(DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY, 1);
+    conf.setInt(DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
+    conf.setInt(DFS_HEARTBEAT_INTERVAL_KEY, 1);
     if (simulatedStorage) {
       conf.setBoolean(SimulatedFSDataset.CONFIG_PROPERTY_SIMULATED, true);
     }
@@ -412,8 +413,8 @@ public class TestFileCreation extends junit.framework.TestCase {
     Configuration conf = new HdfsConfiguration();
     final int MAX_IDLE_TIME = 2000; // 2s
     conf.setInt("ipc.client.connection.maxidletime", MAX_IDLE_TIME);
-    conf.setInt(DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
-    conf.setInt(DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY, 1);
+    conf.setInt(DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
+    conf.setInt(DFS_HEARTBEAT_INTERVAL_KEY, 1);
     if (simulatedStorage) {
       conf.setBoolean(SimulatedFSDataset.CONFIG_PROPERTY_SIMULATED, true);
     }
@@ -724,7 +725,7 @@ public class TestFileCreation extends junit.framework.TestCase {
    */
   public void testFileCreationSyncOnClose() throws IOException {
     Configuration conf = new HdfsConfiguration();
-    conf.setBoolean(DFSConfigKeys.DFS_DATANODE_SYNCONCLOSE_KEY, true);
+    conf.setBoolean(DFS_DATANODE_SYNCONCLOSE_KEY, true);
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
 
     try {
@@ -763,8 +764,8 @@ public class TestFileCreation extends junit.framework.TestCase {
     final int DATANODE_NUM = 3;
 
     Configuration conf = new HdfsConfiguration();
-    conf.setInt(DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
-    conf.setInt(DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY, 1);
+    conf.setInt(DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000);
+    conf.setInt(DFS_HEARTBEAT_INTERVAL_KEY, 1);
 
     // create cluster
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(DATANODE_NUM).build();
@@ -853,7 +854,7 @@ public class TestFileCreation extends junit.framework.TestCase {
     final int DATANODE_NUM = 3;
 
     Configuration conf = new HdfsConfiguration();
-    conf.setInt(DFSConfigKeys.DFS_NAMENODE_REPLICATION_MIN_KEY, 3);
+    conf.setInt(DFS_NAMENODE_REPLICATION_MIN_KEY, 3);
     conf.setBoolean("ipc.client.ping", false); // hdfs timeout is default 60 seconds
     conf.setInt("ipc.ping.interval", 10000); // hdfs timeout is now 10 second
 

hdfs/src/test/hdfs/org/apache/hadoop/hdfs/TestFileStatus.java

@@ -91,7 +91,7 @@ public class TestFileStatus {
       int fileSize, int blockSize) throws IOException {
     // Create and write a file that contains three blocks of data
     FSDataOutputStream stm = fileSys.create(name, true,
-        FSConstants.BUFFER_SIZE, (short)repl, (long)blockSize);
+        FSConstants.IO_FILE_BUFFER_SIZE, (short)repl, (long)blockSize);
     byte[] buffer = new byte[fileSize];
     Random rand = new Random(seed);
     rand.nextBytes(buffer);

hdfs/src/test/hdfs/org/apache/hadoop/hdfs/server/datanode/SimulatedFSDataset.java

@@ -63,7 +63,7 @@ import org.apache.hadoop.util.DiskChecker.DiskErrorException;
  * Note the synchronization is coarse grained - it is at each method. 
  */
 
-public class SimulatedFSDataset  implements FSConstants, FSDatasetInterface, Configurable{
+public class SimulatedFSDataset  implements FSDatasetInterface, Configurable{
   
   public static final String CONFIG_PROPERTY_SIMULATED =
                                     "dfs.datanode.simulateddatastorage";