/**
    *
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.hadoop.hbase;
  
  import java.io.ByteArrayInputStream;
  import java.io.DataInput;
  import java.io.DataInputStream;
  import java.io.DataOutput;
  import java.io.EOFException;
  import java.io.IOException;
  import java.io.SequenceInputStream;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.List;
  
  import org.apache.hadoop.hbase.util.ByteStringer;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.classification.InterfaceStability;
  import org.apache.hadoop.hbase.KeyValue.KVComparator;
  import org.apache.hadoop.hbase.client.RegionReplicaUtil;
  import org.apache.hadoop.hbase.client.Result;
  import org.apache.hadoop.hbase.exceptions.DeserializationException;
  import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
  import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos;
  import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.RegionInfo;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.apache.hadoop.hbase.util.JenkinsHash;
  import org.apache.hadoop.hbase.util.MD5Hash;
  import org.apache.hadoop.hbase.util.Pair;
  import org.apache.hadoop.hbase.util.PairOfSameType;
  import org.apache.hadoop.io.DataInputBuffer;
  
  /**
   * Information about a region. A region is a range of keys in the whole keyspace of a table, an
   * identifier (a timestamp) for differentiating between subset ranges (after region split)
   * and a replicaId for differentiating the instance for the same range and some status information
   * about the region.
   *
   * The region has a unique name which consists of the following fields:
   * <li> tableName   : The name of the table </li>
   * <li> startKey    : The startKey for the region. </li>
   * <li> regionId    : A timestamp when the region is created. </li>
   * <li> replicaId   : An id starting from 0 to differentiate replicas of the same region range
   * but hosted in separated servers. The same region range can be hosted in multiple locations.</li>
   * <li> encodedName : An MD5 encoded string for the region name.</li>
   *
   * <br> Other than the fields in the region name, region info contains:
   * <li> endKey      : the endKey for the region (exclusive) </li>
   * <li> split       : Whether the region is split </li>
   * <li> offline     : Whether the region is offline </li>
   *
   * In 0.98 or before, a list of table's regions would fully cover the total keyspace, and at any
   * point in time, a row key always belongs to a single region, which is hosted in a single server.
   * In 0.99+, a region can have multiple instances (called replicas), and thus a range (or row) can
   * correspond to multiple HRegionInfo's. These HRI's share the same fields however except the
   * replicaId field. If the replicaId is not set, it defaults to 0, which is compatible with the
   * previous behavior of a range corresponding to 1 region.
   */
  @InterfaceAudience.Public
  @InterfaceStability.Evolving
  public class HRegionInfo implements Comparable<HRegionInfo> {
    /*
     * There are two versions associated with HRegionInfo: HRegionInfo.VERSION and
     * HConstants.META_VERSION. HRegionInfo.VERSION indicates the data structure's versioning
     * while HConstants.META_VERSION indicates the versioning of the serialized HRIs stored in
     * the hbase:meta table.
     *
     * Pre-0.92:
     *   HRI.VERSION == 0 and HConstants.META_VERSION does not exist
      *  (is not stored at hbase:meta table)
     *   HRegionInfo had an HTableDescriptor reference inside it.
     *   HRegionInfo is serialized as Writable to hbase:meta table.
     * For 0.92.x and 0.94.x:
     *   HRI.VERSION == 1 and HConstants.META_VERSION == 0
     *   HRI no longer has HTableDescriptor in it.
     *   HRI is serialized as Writable to hbase:meta table.
     * For 0.96.x:
     *   HRI.VERSION == 1 and HConstants.META_VERSION == 1
     *   HRI data structure is the same as 0.92 and 0.94
     *   HRI is serialized as PB to hbase:meta table.
     *
    * Versioning of HRegionInfo is deprecated. HRegionInfo does protobuf
    * serialization using RegionInfo class, which has it's own versioning.
    */
   @Deprecated
   public static final byte VERSION = 1;
   private static final Log LOG = LogFactory.getLog(HRegionInfo.class);
 
   /**
    * The new format for a region name contains its encodedName at the end.
    * The encoded name also serves as the directory name for the region
    * in the filesystem.
    *
    * New region name format:
    *    &lt;tablename>,,&lt;startkey>,&lt;regionIdTimestamp>.&lt;encodedName>.
    * where,
    *    &lt;encodedName> is a hex version of the MD5 hash of
    *    &lt;tablename>,&lt;startkey>,&lt;regionIdTimestamp>
    *
    * The old region name format:
    *    &lt;tablename>,&lt;startkey>,&lt;regionIdTimestamp>
    * For region names in the old format, the encoded name is a 32-bit
    * JenkinsHash integer value (in its decimal notation, string form).
    *<p>
    * **NOTE**
    *
    * The first hbase:meta region, and regions created by an older
    * version of HBase (0.20 or prior) will continue to use the
    * old region name format.
    */
 
   /** Separator used to demarcate the encodedName in a region name
    * in the new format. See description on new format above.
    */
   private static final int ENC_SEPARATOR = '.';
   public  static final int MD5_HEX_LENGTH   = 32;
 
   /** A non-capture group so that this can be embedded. */
   public static final String ENCODED_REGION_NAME_REGEX = "(?:[a-f0-9]+)";
 
   // to keep appended int's sorted in string format. Only allows 2 bytes to be
   // sorted for replicaId
   public static final String REPLICA_ID_FORMAT = "%04X";
 
   public static final byte REPLICA_ID_DELIMITER = (byte)'_';
 
   private static final int MAX_REPLICA_ID = 0xFFFF;
   public static final int DEFAULT_REPLICA_ID = 0;
   /**
    * Does region name contain its encoded name?
    * @param regionName region name
    * @return boolean indicating if this a new format region
    *         name which contains its encoded name.
    */
   private static boolean hasEncodedName(final byte[] regionName) {
     // check if region name ends in ENC_SEPARATOR
     if ((regionName.length >= 1)
         && (regionName[regionName.length - 1] == ENC_SEPARATOR)) {
       // region name is new format. it contains the encoded name.
       return true;
     }
     return false;
   }
 
   /**
    * @param regionName
    * @return the encodedName
    */
   public static String encodeRegionName(final byte [] regionName) {
     String encodedName;
     if (hasEncodedName(regionName)) {
       // region is in new format:
       // <tableName>,<startKey>,<regionIdTimeStamp>/encodedName/
       encodedName = Bytes.toString(regionName,
           regionName.length - MD5_HEX_LENGTH - 1,
           MD5_HEX_LENGTH);
     } else {
       // old format region name. First hbase:meta region also
       // use this format.EncodedName is the JenkinsHash value.
       int hashVal = Math.abs(JenkinsHash.getInstance().hash(regionName,
         regionName.length, 0));
       encodedName = String.valueOf(hashVal);
     }
     return encodedName;
   }
 
   /**
    * @return Return a short, printable name for this region (usually encoded name) for us logging.
    */
   public String getShortNameToLog() {
     return prettyPrint(this.getEncodedName());
   }
 
   /**
    * Use logging.
    * @param encodedRegionName The encoded regionname.
    * @return <code>hbase:meta</code> if passed <code>1028785192</code> else returns
    * <code>encodedRegionName</code>
    */
   public static String prettyPrint(final String encodedRegionName) {
     if (encodedRegionName.equals("1028785192")) {
       return encodedRegionName + "/hbase:meta";
     }
     return encodedRegionName;
   }
 
   private byte [] endKey = HConstants.EMPTY_BYTE_ARRAY;
   // This flag is in the parent of a split while the parent is still referenced
   // by daughter regions.  We USED to set this flag when we disabled a table
   // but now table state is kept up in zookeeper as of 0.90.0 HBase.
   private boolean offLine = false;
   private long regionId = -1;
   private transient byte [] regionName = HConstants.EMPTY_BYTE_ARRAY;
   private boolean split = false;
   private byte [] startKey = HConstants.EMPTY_BYTE_ARRAY;
   private int hashCode = -1;
   //TODO: Move NO_HASH to HStoreFile which is really the only place it is used.
   public static final String NO_HASH = null;
   private String encodedName = null;
   private byte [] encodedNameAsBytes = null;
   private int replicaId = DEFAULT_REPLICA_ID;
 
   // Current TableName
   private TableName tableName = null;
 
   /** HRegionInfo for first meta region */
   // TODO: How come Meta regions still do not have encoded region names? Fix.
   public static final HRegionInfo FIRST_META_REGIONINFO =
       new HRegionInfo(1L, TableName.META_TABLE_NAME);
 
   private void setHashCode() {
     int result = Arrays.hashCode(this.regionName);
     result ^= this.regionId;
     result ^= Arrays.hashCode(this.startKey);
     result ^= Arrays.hashCode(this.endKey);
     result ^= Boolean.valueOf(this.offLine).hashCode();
     result ^= Arrays.hashCode(this.tableName.getName());
     result ^= this.replicaId;
     this.hashCode = result;
   }
 
 
   /**
    * Private constructor used constructing HRegionInfo for the
    * first meta regions
    */
   private HRegionInfo(long regionId, TableName tableName) {
     this(regionId, tableName, DEFAULT_REPLICA_ID);
   }
 
   public HRegionInfo(long regionId, TableName tableName, int replicaId) {
     super();
     this.regionId = regionId;
     this.tableName = tableName;
     this.replicaId = replicaId;
     // Note: First Meta region replicas names are in old format
     this.regionName = createRegionName(tableName, null, regionId, replicaId, false);
     setHashCode();
   }
 
   /** Default constructor - creates empty object
    * @deprecated As of release 0.96
    *             (<a href="https://issues.apache.org/jira/browse/HBASE-5453">HBASE-5453</a>).
    *             This will be removed in HBase 2.0.0.
    *             Used by Writables and Writables are going away.
    */
   @Deprecated
   public HRegionInfo() {
     super();
   }
 
   public HRegionInfo(final TableName tableName) {
     this(tableName, null, null);
   }
 
   /**
    * Construct HRegionInfo with explicit parameters
    *
    * @param tableName the table name
    * @param startKey first key in region
    * @param endKey end of key range
    * @throws IllegalArgumentException
    */
   public HRegionInfo(final TableName tableName, final byte[] startKey, final byte[] endKey)
   throws IllegalArgumentException {
     this(tableName, startKey, endKey, false);
   }
 
   /**
    * Construct HRegionInfo with explicit parameters
    *
    * @param tableName the table descriptor
    * @param startKey first key in region
    * @param endKey end of key range
    * @param split true if this region has split and we have daughter regions
    * regions that may or may not hold references to this region.
    * @throws IllegalArgumentException
    */
   public HRegionInfo(final TableName tableName, final byte[] startKey, final byte[] endKey,
       final boolean split)
   throws IllegalArgumentException {
     this(tableName, startKey, endKey, split, System.currentTimeMillis());
   }
 
   /**
    * Construct HRegionInfo with explicit parameters
    *
    * @param tableName the table descriptor
    * @param startKey first key in region
    * @param endKey end of key range
    * @param split true if this region has split and we have daughter regions
    * regions that may or may not hold references to this region.
    * @param regionid Region id to use.
    * @throws IllegalArgumentException
    */
   public HRegionInfo(final TableName tableName, final byte[] startKey,
                      final byte[] endKey, final boolean split, final long regionid)
   throws IllegalArgumentException {
     this(tableName, startKey, endKey, split, regionid, DEFAULT_REPLICA_ID);
   }
 
   /**
    * Construct HRegionInfo with explicit parameters
    *
    * @param tableName the table descriptor
    * @param startKey first key in region
    * @param endKey end of key range
    * @param split true if this region has split and we have daughter regions
    * regions that may or may not hold references to this region.
    * @param regionid Region id to use.
    * @param replicaId the replicaId to use
    * @throws IllegalArgumentException
    */
   public HRegionInfo(final TableName tableName, final byte[] startKey,
                      final byte[] endKey, final boolean split, final long regionid,
                      final int replicaId)
     throws IllegalArgumentException {
     super();
     if (tableName == null) {
       throw new IllegalArgumentException("TableName cannot be null");
     }
     this.tableName = tableName;
     this.offLine = false;
     this.regionId = regionid;
     this.replicaId = replicaId;
     if (this.replicaId > MAX_REPLICA_ID) {
       throw new IllegalArgumentException("ReplicaId cannot be greater than" + MAX_REPLICA_ID);
     }
 
     this.regionName = createRegionName(this.tableName, startKey, regionId, replicaId, true);
 
     this.split = split;
     this.endKey = endKey == null? HConstants.EMPTY_END_ROW: endKey.clone();
     this.startKey = startKey == null?
       HConstants.EMPTY_START_ROW: startKey.clone();
     this.tableName = tableName;
     setHashCode();
   }
 
   /**
    * Costruct a copy of another HRegionInfo
    *
    * @param other
    */
   public HRegionInfo(HRegionInfo other) {
     super();
     this.endKey = other.getEndKey();
     this.offLine = other.isOffline();
     this.regionId = other.getRegionId();
     this.regionName = other.getRegionName();
     this.split = other.isSplit();
     this.startKey = other.getStartKey();
     this.hashCode = other.hashCode();
     this.encodedName = other.getEncodedName();
     this.tableName = other.tableName;
     this.replicaId = other.replicaId;
   }
 
   public HRegionInfo(HRegionInfo other, int replicaId) {
     this(other);
     this.replicaId = replicaId;
     this.setHashCode();
   }
 
   /**
    * Make a region name of passed parameters.
    * @param tableName
    * @param startKey Can be null
    * @param regionid Region id (Usually timestamp from when region was created).
    * @param newFormat should we create the region name in the new format
    *                  (such that it contains its encoded name?).
    * @return Region name made of passed tableName, startKey and id
    */
   public static byte [] createRegionName(final TableName tableName,
       final byte [] startKey, final long regionid, boolean newFormat) {
     return createRegionName(tableName, startKey, Long.toString(regionid), newFormat);
   }
 
   /**
    * Make a region name of passed parameters.
    * @param tableName
    * @param startKey Can be null
    * @param id Region id (Usually timestamp from when region was created).
    * @param newFormat should we create the region name in the new format
    *                  (such that it contains its encoded name?).
    * @return Region name made of passed tableName, startKey and id
    */
   public static byte [] createRegionName(final TableName tableName,
       final byte [] startKey, final String id, boolean newFormat) {
     return createRegionName(tableName, startKey, Bytes.toBytes(id), newFormat);
   }
 
   /**
    * Make a region name of passed parameters.
    * @param tableName
    * @param startKey Can be null
    * @param regionid Region id (Usually timestamp from when region was created).
    * @param replicaId
    * @param newFormat should we create the region name in the new format
    *                  (such that it contains its encoded name?).
    * @return Region name made of passed tableName, startKey, id and replicaId
    */
   public static byte [] createRegionName(final TableName tableName,
       final byte [] startKey, final long regionid, int replicaId, boolean newFormat) {
     return createRegionName(tableName, startKey, Bytes.toBytes(Long.toString(regionid)),
         replicaId, newFormat);
   }
 
   /**
    * Make a region name of passed parameters.
    * @param tableName
    * @param startKey Can be null
    * @param id Region id (Usually timestamp from when region was created).
    * @param newFormat should we create the region name in the new format
    *                  (such that it contains its encoded name?).
    * @return Region name made of passed tableName, startKey and id
    */
   public static byte [] createRegionName(final TableName tableName,
       final byte [] startKey, final byte [] id, boolean newFormat) {
     return createRegionName(tableName, startKey, id, DEFAULT_REPLICA_ID, newFormat);
   }
   /**
    * Make a region name of passed parameters.
    * @param tableName
    * @param startKey Can be null
    * @param id Region id (Usually timestamp from when region was created).
    * @param replicaId
    * @param newFormat should we create the region name in the new format
    * @return Region name made of passed tableName, startKey, id and replicaId
    */
   public static byte [] createRegionName(final TableName tableName,
       final byte [] startKey, final byte [] id, final int replicaId, boolean newFormat) {
     int len = tableName.getName().length + 2 + id.length +
         (startKey == null? 0: startKey.length);
     if (newFormat) {
       len += MD5_HEX_LENGTH + 2;
     }
     byte[] replicaIdBytes = null;
     // Special casing: replicaId is only appended if replicaId is greater than
     // 0. This is because all regions in meta would have to be migrated to the new
     // name otherwise
     if (replicaId > 0) {
       // use string representation for replica id
       replicaIdBytes = Bytes.toBytes(String.format(REPLICA_ID_FORMAT, replicaId));
       len += 1 + replicaIdBytes.length;
     }
 
     byte [] b = new byte [len];
 
     int offset = tableName.getName().length;
     System.arraycopy(tableName.getName(), 0, b, 0, offset);
     b[offset++] = HConstants.DELIMITER;
     if (startKey != null && startKey.length > 0) {
       System.arraycopy(startKey, 0, b, offset, startKey.length);
       offset += startKey.length;
     }
     b[offset++] = HConstants.DELIMITER;
     System.arraycopy(id, 0, b, offset, id.length);
     offset += id.length;
 
     if (replicaIdBytes != null) {
       b[offset++] = REPLICA_ID_DELIMITER;
       System.arraycopy(replicaIdBytes, 0, b, offset, replicaIdBytes.length);
       offset += replicaIdBytes.length;
     }
 
     if (newFormat) {
       //
       // Encoded name should be built into the region name.
       //
       // Use the region name thus far (namely, <tablename>,<startKey>,<id>_<replicaId>)
       // to compute a MD5 hash to be used as the encoded name, and append
       // it to the byte buffer.
       //
       String md5Hash = MD5Hash.getMD5AsHex(b, 0, offset);
       byte [] md5HashBytes = Bytes.toBytes(md5Hash);
 
       if (md5HashBytes.length != MD5_HEX_LENGTH) {
         LOG.error("MD5-hash length mismatch: Expected=" + MD5_HEX_LENGTH +
                   "; Got=" + md5HashBytes.length);
       }
 
       // now append the bytes '.<encodedName>.' to the end
       b[offset++] = ENC_SEPARATOR;
       System.arraycopy(md5HashBytes, 0, b, offset, MD5_HEX_LENGTH);
       offset += MD5_HEX_LENGTH;
       b[offset++] = ENC_SEPARATOR;
     }
 
     return b;
   }
 
   /**
    * Gets the table name from the specified region name.
    * @param regionName
    * @return Table name.
    * @deprecated As of release 0.96
    *             (<a href="https://issues.apache.org/jira/browse/HBASE-9508">HBASE-9508</a>).
    *             This will be removed in HBase 2.0.0. Use {@link #getTable(byte[])}.
    */
   @Deprecated
   public static byte [] getTableName(byte[] regionName) {
     int offset = -1;
     for (int i = 0; i < regionName.length; i++) {
       if (regionName[i] == HConstants.DELIMITER) {
         offset = i;
         break;
       }
     }
     byte[] buff  = new byte[offset];
     System.arraycopy(regionName, 0, buff, 0, offset);
     return buff;
   }
 
 
   /**
    * Gets the table name from the specified region name.
    * Like {@link #getTableName(byte[])} only returns a {@link TableName} rather than a byte array.
    * @param regionName
    * @return Table name
    * @see #getTableName(byte[])
    */
   public static TableName getTable(final byte [] regionName) {
     return TableName.valueOf(getTableName(regionName));
   }
 
   /**
    * Gets the start key from the specified region name.
    * @param regionName
    * @return Start key.
    */
   public static byte[] getStartKey(final byte[] regionName) throws IOException {
     return parseRegionName(regionName)[1];
   }
 
   /**
    * Separate elements of a regionName.
    * @param regionName
    * @return Array of byte[] containing tableName, startKey and id
    * @throws IOException
    */
   public static byte [][] parseRegionName(final byte [] regionName)
   throws IOException {
     // Region name is of the format:
     // tablename,startkey,regionIdTimestamp[_replicaId][.encodedName.]
     // startkey can contain the delimiter (',') so we parse from the start and end
 
     // parse from start
     int offset = -1;
     for (int i = 0; i < regionName.length; i++) {
       if (regionName[i] == HConstants.DELIMITER) {
         offset = i;
         break;
       }
     }
     if (offset == -1) {
       throw new IOException("Invalid regionName format: " + Bytes.toStringBinary(regionName));
     }
     byte[] tableName = new byte[offset];
     System.arraycopy(regionName, 0, tableName, 0, offset);
     offset = -1;
 
     int endOffset = regionName.length;
     // check whether regionName contains encodedName
     if (regionName.length > MD5_HEX_LENGTH + 2
         && regionName[regionName.length-1] == ENC_SEPARATOR
         && regionName[regionName.length-MD5_HEX_LENGTH-2] == ENC_SEPARATOR) {
       endOffset = endOffset - MD5_HEX_LENGTH - 2;
     }
 
     // parse from end
     byte[] replicaId = null;
     int idEndOffset = endOffset;
     for (int i = endOffset - 1; i > 0; i--) {
       if (regionName[i] == REPLICA_ID_DELIMITER) { //replicaId may or may not be present
         replicaId = new byte[endOffset - i - 1];
         System.arraycopy(regionName, i + 1, replicaId, 0,
           endOffset - i - 1);
         idEndOffset = i;
         // do not break, continue to search for id
       }
       if (regionName[i] == HConstants.DELIMITER) {
         offset = i;
         break;
       }
     }
     if (offset == -1) {
       throw new IOException("Invalid regionName format: " + Bytes.toStringBinary(regionName));
     }
     byte [] startKey = HConstants.EMPTY_BYTE_ARRAY;
     if(offset != tableName.length + 1) {
       startKey = new byte[offset - tableName.length - 1];
       System.arraycopy(regionName, tableName.length + 1, startKey, 0,
           offset - tableName.length - 1);
     }
     byte [] id = new byte[idEndOffset - offset - 1];
     System.arraycopy(regionName, offset + 1, id, 0,
       idEndOffset - offset - 1);
     byte [][] elements = new byte[replicaId == null ? 3 : 4][];
     elements[0] = tableName;
     elements[1] = startKey;
     elements[2] = id;
     if (replicaId != null) {
       elements[3] = replicaId;
     }
 
     return elements;
   }
 
   /** @return the regionId */
   public long getRegionId(){
     return regionId;
   }
 
   /**
    * @return the regionName as an array of bytes.
    * @see #getRegionNameAsString()
    */
   public byte [] getRegionName(){
     return regionName;
   }
 
   /**
    * @return Region name as a String for use in logging, etc.
    */
   public String getRegionNameAsString() {
     if (hasEncodedName(this.regionName)) {
       // new format region names already have their encoded name.
       return Bytes.toStringBinary(this.regionName);
     }
 
     // old format. regionNameStr doesn't have the region name.
     //
     //
     return Bytes.toStringBinary(this.regionName) + "." + this.getEncodedName();
   }
 
   /** @return the encoded region name */
   public synchronized String getEncodedName() {
     if (this.encodedName == null) {
       this.encodedName = encodeRegionName(this.regionName);
     }
     return this.encodedName;
   }
 
   public synchronized byte [] getEncodedNameAsBytes() {
     if (this.encodedNameAsBytes == null) {
       this.encodedNameAsBytes = Bytes.toBytes(getEncodedName());
     }
     return this.encodedNameAsBytes;
   }
 
   /** @return the startKey */
   public byte [] getStartKey(){
     return startKey;
   }
 
   /** @return the endKey */
   public byte [] getEndKey(){
     return endKey;
   }
 
   /**
    * Get current table name of the region
    * @return byte array of table name
    * @deprecated As of release 0.96
    *             (<a href="https://issues.apache.org/jira/browse/HBASE-9508">HBASE-9508</a>).
    *             This will be removed in HBase 2.0.0. Use {@link #getTable()}.
    */
   @Deprecated
   public byte [] getTableName() {
     return getTable().toBytes();
   }
 
   /**
    * Get current table name of the region
    * @return TableName
    * @see #getTableName()
    */
   public TableName getTable() {
     // This method name should be getTableName but there was already a method getTableName
     // that returned a byte array.  It is unfortunate given everwhere else, getTableName returns
     // a TableName instance.
     if (tableName == null || tableName.getName().length == 0) {
       tableName = getTable(getRegionName());
     }
     return this.tableName;
   }
 
   /**
    * Returns true if the given inclusive range of rows is fully contained
    * by this region. For example, if the region is foo,a,g and this is
    * passed ["b","c"] or ["a","c"] it will return true, but if this is passed
    * ["b","z"] it will return false.
    * @throws IllegalArgumentException if the range passed is invalid (ie end < start)
    */
   public boolean containsRange(byte[] rangeStartKey, byte[] rangeEndKey) {
     if (Bytes.compareTo(rangeStartKey, rangeEndKey) > 0) {
       throw new IllegalArgumentException(
       "Invalid range: " + Bytes.toStringBinary(rangeStartKey) +
       " > " + Bytes.toStringBinary(rangeEndKey));
     }
 
     boolean firstKeyInRange = Bytes.compareTo(rangeStartKey, startKey) >= 0;
     boolean lastKeyInRange =
       Bytes.compareTo(rangeEndKey, endKey) < 0 ||
       Bytes.equals(endKey, HConstants.EMPTY_BYTE_ARRAY);
     return firstKeyInRange && lastKeyInRange;
   }
 
   /**
    * Return true if the given row falls in this region.
    */
   public boolean containsRow(byte[] row) {
     return Bytes.compareTo(row, startKey) >= 0 &&
       (Bytes.compareTo(row, endKey) < 0 ||
        Bytes.equals(endKey, HConstants.EMPTY_BYTE_ARRAY));
   }
 
   /**
    * @return true if this region is from hbase:meta
    */
   public boolean isMetaTable() {
     return isMetaRegion();
   }
 
   /** @return true if this region is a meta region */
   public boolean isMetaRegion() {
      return tableName.equals(HRegionInfo.FIRST_META_REGIONINFO.getTable());
   }
 
   /**
    * @return true if this region is from a system table
    */
   public boolean isSystemTable() {
     return tableName.isSystemTable();
   }
 
   /**
    * @return True if has been split and has daughters.
    */
   public boolean isSplit() {
     return this.split;
   }
 
   /**
    * @param split set split status
    */
   public void setSplit(boolean split) {
     this.split = split;
   }
 
   /**
    * @return True if this region is offline.
    */
   public boolean isOffline() {
     return this.offLine;
   }
 
   /**
    * The parent of a region split is offline while split daughters hold
    * references to the parent. Offlined regions are closed.
    * @param offLine Set online/offline status.
    */
   public void setOffline(boolean offLine) {
     this.offLine = offLine;
   }
 
   /**
    * @return True if this is a split parent region.
    */
   public boolean isSplitParent() {
     if (!isSplit()) return false;
     if (!isOffline()) {
       LOG.warn("Region is split but NOT offline: " + getRegionNameAsString());
     }
     return true;
   }
 
   /**
    * Returns the region replica id
    * @return returns region replica id
    */
   public int getReplicaId() {
     return replicaId;
   }
 
   /**
    * @see java.lang.Object#toString()
    */
   @Override
   public String toString() {
     return "{ENCODED => " + getEncodedName() + ", " +
       HConstants.NAME + " => '" + Bytes.toStringBinary(this.regionName)
       + "', STARTKEY => '" +
       Bytes.toStringBinary(this.startKey) + "', ENDKEY => '" +
       Bytes.toStringBinary(this.endKey) + "'" +
       (isOffline()? ", OFFLINE => true": "") +
       (isSplit()? ", SPLIT => true": "") +
       ((replicaId > 0)? ", REPLICA_ID => " + replicaId : "") + "}";
   }
 
   /**
    * @see java.lang.Object#equals(java.lang.Object)
    */
   @Override
   public boolean equals(Object o) {
     if (this == o) {
       return true;
     }
     if (o == null) {
       return false;
     }
     if (!(o instanceof HRegionInfo)) {
       return false;
     }
     return this.compareTo((HRegionInfo)o) == 0;
   }
 
   /**
    * @see java.lang.Object#hashCode()
    */
   @Override
   public int hashCode() {
     return this.hashCode;
   }
 
   /** @return the object version number
    * @deprecated HRI is no longer a VersionedWritable */
   @Deprecated
   public byte getVersion() {
     return VERSION;
   }
 
   /**
    * @deprecated Use protobuf serialization instead.  See {@link #toByteArray()} and
    * {@link #toDelimitedByteArray()}
    */
   @Deprecated
   public void write(DataOutput out) throws IOException {
     out.writeByte(getVersion());
     Bytes.writeByteArray(out, endKey);
     out.writeBoolean(offLine);
     out.writeLong(regionId);
     Bytes.writeByteArray(out, regionName);
     out.writeBoolean(split);
     Bytes.writeByteArray(out, startKey);
     Bytes.writeByteArray(out, tableName.getName());
     out.writeInt(hashCode);
   }
 
   /**
    * @deprecated Use protobuf deserialization instead.
    * @see #parseFrom(byte[])
    */
   @Deprecated
   public void readFields(DataInput in) throws IOException {
     // Read the single version byte.  We don't ask the super class do it
     // because freaks out if its not the current classes' version.  This method
     // can deserialize version 0 and version 1 of HRI.
     byte version = in.readByte();
     if (version == 0) {
       // This is the old HRI that carried an HTD.  Migrate it.  The below
       // was copied from the old 0.90 HRI readFields.
       this.endKey = Bytes.readByteArray(in);
       this.offLine = in.readBoolean();
       this.regionId = in.readLong();
       this.regionName = Bytes.readByteArray(in);
       this.split = in.readBoolean();
       this.startKey = Bytes.readByteArray(in);
       try {
         HTableDescriptor htd = new HTableDescriptor();
         htd.readFields(in);
         this.tableName = htd.getTableName();
       } catch(EOFException eofe) {
          throw new IOException("HTD not found in input buffer", eofe);
       }
       this.hashCode = in.readInt();
     } else if (getVersion() == version) {
       this.endKey = Bytes.readByteArray(in);
       this.offLine = in.readBoolean();
       this.regionId = in.readLong();
       this.regionName = Bytes.readByteArray(in);
       this.split = in.readBoolean();
       this.startKey = Bytes.readByteArray(in);
       this.tableName = TableName.valueOf(Bytes.readByteArray(in));
       this.hashCode = in.readInt();
     } else {
       throw new IOException("Non-migratable/unknown version=" + getVersion());
     }
   }
 
   @Deprecated
   private void readFields(byte[] bytes, int offset, int len) throws IOException {
     if (bytes == null || len <= 0) {
       throw new IllegalArgumentException("Can't build a writable with empty " +
           "bytes array");
     }
     DataInputBuffer in = new DataInputBuffer();
     try {
       in.reset(bytes, offset, len);
       this.readFields(in);
     } finally {
       in.close();
     }
   }
 
   //
   // Comparable
   //
 
   @Override
   public int compareTo(HRegionInfo o) {
     if (o == null) {
       return 1;
     }
 
     // Are regions of same table?
     int result = this.tableName.compareTo(o.tableName);
     if (result != 0) {
       return result;
     }
 
     // Compare start keys.
     result = Bytes.compareTo(this.startKey, o.startKey);
     if (result != 0) {
       return result;
     }
 
     // Compare end keys.
     result = Bytes.compareTo(this.endKey, o.endKey);
 
     if (result != 0) {
       if (this.getStartKey().length != 0
               && this.getEndKey().length == 0) {
           return 1; // this is last region
       }
       if (o.getStartKey().length != 0
               && o.getEndKey().length == 0) {
           return -1; // o is the last region
       }
       return result;
     }
 
     // regionId is usually milli timestamp -- this defines older stamps
     // to be "smaller" than newer stamps in sort order.
     if (this.regionId > o.regionId) {
       return 1;
     } else if (this.regionId < o.regionId) {
       return -1;
     }
 
     int replicaDiff = this.getReplicaId() - o.getReplicaId();
     if (replicaDiff != 0) return replicaDiff;
 
     if (this.offLine == o.offLine)
       return 0;
     if (this.offLine == true) return -1;
 
     return 1;
   }
 
   /**
    * @return Comparator to use comparing {@link KeyValue}s.
    */
   public KVComparator getComparator() {
     return isMetaRegion()?
       KeyValue.META_COMPARATOR: KeyValue.COMPARATOR;
   }
 
   /**
    * Convert a HRegionInfo to a RegionInfo
    *
    * @return the converted RegionInfo
    */
   RegionInfo convert() {
     return convert(this);
   }
 
   /**
    * Convert a HRegionInfo to a RegionInfo
    *
    * @param info the HRegionInfo to convert
    * @return the converted RegionInfo
    */
   public static RegionInfo convert(final HRegionInfo info) {
     if (info == null) return null;
     RegionInfo.Builder builder = RegionInfo.newBuilder();
     builder.setTableName(ProtobufUtil.toProtoTableName(info.getTable()));
     builder.setRegionId(info.getRegionId());
     if (info.getStartKey() != null) {
       builder.setStartKey(ByteStringer.wrap(info.getStartKey()));
     }
     if (info.getEndKey() != null) {
       builder.setEndKey(ByteStringer.wrap(info.getEndKey()));
     }
     builder.setOffline(info.isOffline());
     builder.setSplit(info.isSplit());
     builder.setReplicaId(info.getReplicaId());
     return builder.build();
   }
 
   /**
    * Convert a RegionInfo to a HRegionInfo
    *
    * @param proto the RegionInfo to convert
    * @return the converted HRegionInfho
    */
   public static HRegionInfo convert(final RegionInfo proto) {
     if (proto == null) return null;
     TableName tableName =
         ProtobufUtil.toTableName(proto.getTableName());
     if (tableName.equals(TableName.META_TABLE_NAME)) {
       return RegionReplicaUtil.getRegionInfoForReplica(FIRST_META_REGIONINFO,
           proto.getReplicaId());
     }
     long regionId = proto.getRegionId();
     int replicaId = proto.hasReplicaId() ? proto.getReplicaId() : DEFAULT_REPLICA_ID;
     byte[] startKey = null;
     byte[] endKey = null;
     if (proto.hasStartKey()) {
       startKey = proto.getStartKey().toByteArray();
     }
     if (proto.hasEndKey()) {
       endKey = proto.getEndKey().toByteArray();
     }
     boolean split = false;
     if (proto.hasSplit()) {
       split = proto.getSplit();
     }
     HRegionInfo hri = new HRegionInfo(
         tableName,
         startKey,
         endKey, split, regionId, replicaId);
     if (proto.hasOffline()) {
       hri.setOffline(proto.getOffline());
     }
     return hri;
   }
 
   /**
    * @return This instance serialized as protobuf w/ a magic pb prefix.
    * @see #parseFrom(byte[])
    */
   public byte [] toByteArray() {
     byte [] bytes = convert().toByteArray();
     return ProtobufUtil.prependPBMagic(bytes);
   }
 
   /**
    * @return A deserialized {@link HRegionInfo}
    * or null if we failed deserialize or passed bytes null
    * @see #toByteArray()
    */
   public static HRegionInfo parseFromOrNull(final byte [] bytes) {
     if (bytes == null) return null;
     return parseFromOrNull(bytes, 0, bytes.length);
   }
 
   /**
    * @return A deserialized {@link HRegionInfo} or null
    *  if we failed deserialize or passed bytes null
    * @see #toByteArray()
    */
   public static HRegionInfo parseFromOrNull(final byte [] bytes, int offset, int len) {
     if (bytes == null || len <= 0) return null;
     try {
       return parseFrom(bytes, offset, len);
     } catch (DeserializationException e) {
       return null;
     }
   }
 
   /**
    * @param bytes A pb RegionInfo serialized with a pb magic prefix.
    * @return A deserialized {@link HRegionInfo}
    * @throws DeserializationException
    * @see #toByteArray()
    */
   public static HRegionInfo parseFrom(final byte [] bytes) throws DeserializationException {
     if (bytes == null) return null;
     return parseFrom(bytes, 0, bytes.length);
   }
 
   /**
    * @param bytes A pb RegionInfo serialized with a pb magic prefix.
    * @param offset starting point in the byte array
    * @param len length to read on the byte array
    * @return A deserialized {@link HRegionInfo}
    * @throws DeserializationException
    * @see #toByteArray()
    */
   public static HRegionInfo parseFrom(final byte [] bytes, int offset, int len)
       throws DeserializationException {
     if (ProtobufUtil.isPBMagicPrefix(bytes, offset, len)) {
       int pblen = ProtobufUtil.lengthOfPBMagic();
       try {
         HBaseProtos.RegionInfo.Builder builder = HBaseProtos.RegionInfo.newBuilder();
         ProtobufUtil.mergeFrom(builder, bytes, pblen + offset, len - pblen);
         HBaseProtos.RegionInfo ri = builder.build();
         return convert(ri);
       } catch (IOException e) {
         throw new DeserializationException(e);
       }
     } else {
       try {
         HRegionInfo hri = new HRegionInfo();
         hri.readFields(bytes, offset, len);
         return hri;
       } catch (IOException e) {
         throw new DeserializationException(e);
       }
     }
   }
 
   /**
    * Use this instead of {@link #toByteArray()} when writing to a stream and you want to use
    * the pb mergeDelimitedFrom (w/o the delimiter, pb reads to EOF which may not be what you want).
    * @return This instance serialized as a delimited protobuf w/ a magic pb prefix.
    * @throws IOException
    * @see #toByteArray()
    */
   public byte [] toDelimitedByteArray() throws IOException {
     return ProtobufUtil.toDelimitedByteArray(convert());
   }
 
   /**
    * Extract a HRegionInfo and ServerName from catalog table {@link Result}.
    * @param r Result to pull from
    * @return A pair of the {@link HRegionInfo} and the {@link ServerName}
    * (or null for server address if no address set in hbase:meta).
    * @throws IOException
    * @deprecated use MetaTableAccessor methods for interacting with meta layouts
    */
   @Deprecated
   public static Pair<HRegionInfo, ServerName> getHRegionInfoAndServerName(final Result r) {
     HRegionInfo info =
       getHRegionInfo(r, HConstants.REGIONINFO_QUALIFIER);
     ServerName sn = getServerName(r);
     return new Pair<HRegionInfo, ServerName>(info, sn);
   }
 
   /**
    * Returns HRegionInfo object from the column
    * HConstants.CATALOG_FAMILY:HConstants.REGIONINFO_QUALIFIER of the catalog
    * table Result.
    * @param data a Result object from the catalog table scan
    * @return HRegionInfo or null
    * @deprecated use MetaTableAccessor methods for interacting with meta layouts
    */
   @Deprecated
   public static HRegionInfo getHRegionInfo(Result data) {
     return getHRegionInfo(data, HConstants.REGIONINFO_QUALIFIER);
   }
 
   /**
    * Returns the daughter regions by reading the corresponding columns of the catalog table
    * Result.
    * @param data a Result object from the catalog table scan
    * @return a pair of HRegionInfo or PairOfSameType(null, null) if the region is not a split
    * parent
    * @deprecated use MetaTableAccessor methods for interacting with meta layouts
    */
   @Deprecated
   public static PairOfSameType<HRegionInfo> getDaughterRegions(Result data) throws IOException {
     HRegionInfo splitA = getHRegionInfo(data, HConstants.SPLITA_QUALIFIER);
     HRegionInfo splitB = getHRegionInfo(data, HConstants.SPLITB_QUALIFIER);
 
     return new PairOfSameType<HRegionInfo>(splitA, splitB);
   }
 
   /**
    * Returns the merge regions by reading the corresponding columns of the catalog table
    * Result.
    * @param data a Result object from the catalog table scan
    * @return a pair of HRegionInfo or PairOfSameType(null, null) if the region is not a split
    * parent
    * @deprecated use MetaTableAccessor methods for interacting with meta layouts
    */
   @Deprecated
   public static PairOfSameType<HRegionInfo> getMergeRegions(Result data) throws IOException {
     HRegionInfo mergeA = getHRegionInfo(data, HConstants.MERGEA_QUALIFIER);
     HRegionInfo mergeB = getHRegionInfo(data, HConstants.MERGEB_QUALIFIER);
 
     return new PairOfSameType<HRegionInfo>(mergeA, mergeB);
   }
 
   /**
    * Returns the HRegionInfo object from the column {@link HConstants#CATALOG_FAMILY} and
    * <code>qualifier</code> of the catalog table result.
    * @param r a Result object from the catalog table scan
    * @param qualifier Column family qualifier -- either
    * {@link HConstants#SPLITA_QUALIFIER}, {@link HConstants#SPLITB_QUALIFIER} or
    * {@link HConstants#REGIONINFO_QUALIFIER}.
    * @return An HRegionInfo instance or null.
    * @deprecated use MetaTableAccessor methods for interacting with meta layouts
    */
   @Deprecated
   public static HRegionInfo getHRegionInfo(final Result r, byte [] qualifier) {
     Cell cell = r.getColumnLatestCell(
         HConstants.CATALOG_FAMILY, qualifier);
     if (cell == null) return null;
     return parseFromOrNull(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
   }
 
   /**
    * @deprecated use MetaTableAccessor methods for interacting with meta layouts
    */
   @Deprecated
   public static ServerName getServerName(final Result r) {
     Cell cell = r.getColumnLatestCell(HConstants.CATALOG_FAMILY, HConstants.SERVER_QUALIFIER);
     if (cell == null || cell.getValueLength() == 0) return null;
     String hostAndPort = Bytes.toString(
         cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
     cell = r.getColumnLatestCell(HConstants.CATALOG_FAMILY,
       HConstants.STARTCODE_QUALIFIER);
     if (cell == null || cell.getValueLength() == 0) return null;
     try {
       return ServerName.valueOf(hostAndPort,
           Bytes.toLong(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength()));
     } catch (IllegalArgumentException e) {
       LOG.error("Ignoring invalid region for server " + hostAndPort + "; cell=" + cell, e);
       return null;
     }
   }
 
   /**
    * The latest seqnum that the server writing to meta observed when opening the region.
    * E.g. the seqNum when the result of {@link #getServerName(Result)} was written.
    * @param r Result to pull the seqNum from
    * @return SeqNum, or HConstants.NO_SEQNUM if there's no value written.
    * @deprecated use MetaTableAccessor methods for interacting with meta layouts
    */
   @Deprecated
   public static long getSeqNumDuringOpen(final Result r) {
     Cell cell = r.getColumnLatestCell(HConstants.CATALOG_FAMILY, HConstants.SEQNUM_QUALIFIER);
     if (cell == null || cell.getValueLength() == 0) return HConstants.NO_SEQNUM;
     return Bytes.toLong(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
   }
 
   /**
    * Parses an HRegionInfo instance from the passed in stream.  Presumes the HRegionInfo was
    * serialized to the stream with {@link #toDelimitedByteArray()}
    * @param in
    * @return An instance of HRegionInfo.
    * @throws IOException
    */
   public static HRegionInfo parseFrom(final DataInputStream in) throws IOException {
     // I need to be able to move back in the stream if this is not a pb serialization so I can
     // do the Writable decoding instead.
     int pblen = ProtobufUtil.lengthOfPBMagic();
     byte [] pbuf = new byte[pblen];
     if (in.markSupported()) { //read it with mark()
       in.mark(pblen);
     }
 
     //assumption: if Writable serialization, it should be longer than pblen.
     int read = in.read(pbuf);
     if (read != pblen) throw new IOException("read=" + read + ", wanted=" + pblen);
     if (ProtobufUtil.isPBMagicPrefix(pbuf)) {
       return convert(HBaseProtos.RegionInfo.parseDelimitedFrom(in));
     } else {
         // Presume Writables.  Need to reset the stream since it didn't start w/ pb.
       if (in.markSupported()) {
         in.reset();
         HRegionInfo hri = new HRegionInfo();
         hri.readFields(in);
         return hri;
       } else {
         //we cannot use BufferedInputStream, it consumes more than we read from the underlying IS
         ByteArrayInputStream bais = new ByteArrayInputStream(pbuf);
         SequenceInputStream sis = new SequenceInputStream(bais, in); //concatenate input streams
         HRegionInfo hri = new HRegionInfo();
         hri.readFields(new DataInputStream(sis));
         return hri;
       }
     }
   }
 
   /**
    * Serializes given HRegionInfo's as a byte array. Use this instead of {@link #toByteArray()} when
    * writing to a stream and you want to use the pb mergeDelimitedFrom (w/o the delimiter, pb reads
    * to EOF which may not be what you want). {@link #parseDelimitedFrom(byte[], int, int)} can
    * be used to read back the instances.
    * @param infos HRegionInfo objects to serialize
    * @return This instance serialized as a delimited protobuf w/ a magic pb prefix.
    * @throws IOException
    * @see #toByteArray()
    */
   public static byte[] toDelimitedByteArray(HRegionInfo... infos) throws IOException {
     byte[][] bytes = new byte[infos.length][];
     int size = 0;
     for (int i = 0; i < infos.length; i++) {
       bytes[i] = infos[i].toDelimitedByteArray();
       size += bytes[i].length;
     }
 
     byte[] result = new byte[size];
     int offset = 0;
     for (byte[] b : bytes) {
       System.arraycopy(b, 0, result, offset, b.length);
       offset += b.length;
     }
     return result;
   }
 
   /**
    * Parses all the HRegionInfo instances from the passed in stream until EOF. Presumes the
    * HRegionInfo's were serialized to the stream with {@link #toDelimitedByteArray()}
    * @param bytes serialized bytes
    * @param offset the start offset into the byte[] buffer
    * @param length how far we should read into the byte[] buffer
    * @return All the hregioninfos that are in the byte array. Keeps reading till we hit the end.
    */
   public static List<HRegionInfo> parseDelimitedFrom(final byte[] bytes, final int offset,
       final int length) throws IOException {
     if (bytes == null) {
       throw new IllegalArgumentException("Can't build an object with empty bytes array");
     }
     DataInputBuffer in = new DataInputBuffer();
     List<HRegionInfo> hris = new ArrayList<HRegionInfo>();
     try {
       in.reset(bytes, offset, length);
       while (in.available() > 0) {
         HRegionInfo hri = parseFrom(in);
         hris.add(hri);
       }
     } finally {
       in.close();
     }
     return hris;
   }
 
   /**
    * Check whether two regions are adjacent
    * @param regionA
    * @param regionB
    * @return true if two regions are adjacent
    */
   public static boolean areAdjacent(HRegionInfo regionA, HRegionInfo regionB) {
     if (regionA == null || regionB == null) {
       throw new IllegalArgumentException(
           "Can't check whether adjacent for null region");
     }
     HRegionInfo a = regionA;
     HRegionInfo b = regionB;
     if (Bytes.compareTo(a.getStartKey(), b.getStartKey()) > 0) {
       a = regionB;
       b = regionA;
     }
     if (Bytes.compareTo(a.getEndKey(), b.getStartKey()) == 0) {
       return true;
     }
     return false;
   }
 }