0.90/src/main/java/org/apache/hadoop/hbase/HRegionInfo.java - hbase - Git at Google

 /**
  * Copyright 2007 The Apache Software Foundation
  *
  * 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.DataInput;
 import java.io.DataOutput;
 import java.io.IOException;
 import java.util.Arrays;

 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.hbase.KeyValue.KVComparator;
 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.io.VersionedWritable;
 import org.apache.hadoop.io.WritableComparable;

 /**
  * HRegion information.
  * Contains HRegion id, start and end keys, a reference to this
  * HRegions' table descriptor, etc.
  */
 public class HRegionInfo extends VersionedWritable implements WritableComparable<HRegionInfo>{
   private static final byte VERSION = 0;
   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**
    *
    * ROOT, the first 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;

   /**
    * 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. ROOT and first 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;
   }

   /**
    * Use logging.
    * @param encodedRegionName The encoded regionname.
    * @return <code>-ROOT-</code> if passed <code>70236052</code> or
    * <code>.META.</code> if passed </code>1028785192</code> else returns
    * <code>encodedRegionName</code>
    */
   public static String prettyPrint(final String encodedRegionName) {
     if (encodedRegionName.equals("70236052")) {
       return encodedRegionName + "/-ROOT-";
     } else if (encodedRegionName.equals("1028785192")) {
       return encodedRegionName + "/.META.";
     }
     return encodedRegionName;
   }

   /** delimiter used between portions of a region name */
   public static final int DELIMITER = ',';

   /** HRegionInfo for root region */
   public static final HRegionInfo ROOT_REGIONINFO =
     new HRegionInfo(0L, HTableDescriptor.ROOT_TABLEDESC);

   /** HRegionInfo for first meta region */
   public static final HRegionInfo FIRST_META_REGIONINFO =
     new HRegionInfo(1L, HTableDescriptor.META_TABLEDESC);

   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 String regionNameStr = "";
   private boolean split = false;
   private byte [] startKey = HConstants.EMPTY_BYTE_ARRAY;
   protected HTableDescriptor tableDesc = null;
   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 volatile String encodedName = NO_HASH;
   private byte [] encodedNameAsBytes = null;

   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 ^= this.tableDesc.hashCode();
     this.hashCode = result;
   }

   /**
    * Private constructor used constructing HRegionInfo for the catalog root and
    * first meta regions
    */
   private HRegionInfo(long regionId, HTableDescriptor tableDesc) {
     super();
     this.regionId = regionId;
     this.tableDesc = tableDesc;

     // Note: Root & First Meta regions names are still in old format
     this.regionName = createRegionName(tableDesc.getName(), null,
                                        regionId, false);
     this.regionNameStr = Bytes.toStringBinary(this.regionName);
     setHashCode();
   }

   /** Default constructor - creates empty object */
   public HRegionInfo() {
     super();
     this.tableDesc = new HTableDescriptor();
   }

   /**
    * Construct HRegionInfo with explicit parameters
    *
    * @param tableDesc the table descriptor
    * @param startKey first key in region
    * @param endKey end of key range
    * @throws IllegalArgumentException
    */
   public HRegionInfo(final HTableDescriptor tableDesc, final byte [] startKey,
       final byte [] endKey)
   throws IllegalArgumentException {
     this(tableDesc, startKey, endKey, false);
   }

   /**
    * Construct HRegionInfo with explicit parameters
    *
    * @param tableDesc 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(HTableDescriptor tableDesc, final byte [] startKey,
       final byte [] endKey, final boolean split)
   throws IllegalArgumentException {
     this(tableDesc, startKey, endKey, split, System.currentTimeMillis());
   }

   /**
    * Construct HRegionInfo with explicit parameters
    *
    * @param tableDesc 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(HTableDescriptor tableDesc, final byte [] startKey,
     final byte [] endKey, final boolean split, final long regionid)
   throws IllegalArgumentException {
     super();
     if (tableDesc == null) {
       throw new IllegalArgumentException("tableDesc cannot be null");
     }
     this.offLine = false;
     this.regionId = regionid;
     this.regionName = createRegionName(tableDesc.getName(), startKey, regionId, true);
     this.regionNameStr = Bytes.toStringBinary(this.regionName);
     this.split = split;
     this.endKey = endKey == null? HConstants.EMPTY_END_ROW: endKey.clone();
     this.startKey = startKey == null?
       HConstants.EMPTY_START_ROW: startKey.clone();
     this.tableDesc = tableDesc;
     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.regionNameStr = Bytes.toStringBinary(this.regionName);
     this.split = other.isSplit();
     this.startKey = other.getStartKey();
     this.tableDesc = other.getTableDesc();
     this.hashCode = other.hashCode();
     this.encodedName = other.getEncodedName();
   }

   /**
    * 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 byte [] 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 byte [] 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 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 byte [] tableName,
       final byte [] startKey, final byte [] id, boolean newFormat) {
     byte [] b = new byte [tableName.length + 2 + id.length +
        (startKey == null? 0: startKey.length) +
        (newFormat ? (MD5_HEX_LENGTH + 2) : 0)];

     int offset = tableName.length;
     System.arraycopy(tableName, 0, b, 0, offset);
     b[offset++] = DELIMITER;
     if (startKey != null && startKey.length > 0) {
       System.arraycopy(startKey, 0, b, offset, startKey.length);
       offset += startKey.length;
     }
     b[offset++] = DELIMITER;
     System.arraycopy(id, 0, b, offset, id.length);
     offset += id.length;

     if (newFormat) {
       //
       // Encoded name should be built into the region name.
       //
       // Use the region name thus far (namely, <tablename>,<startKey>,<id>)
       // 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.
    */
   public static byte [] getTableName(byte [] regionName) {
     int offset = -1;
     for (int i = 0; i < regionName.length; i++) {
       if (regionName[i] == DELIMITER) {
         offset = i;
         break;
       }
     }
     byte [] tableName = new byte[offset];
     System.arraycopy(regionName, 0, tableName, 0, offset);
     return tableName;
   }

   /**
    * 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 {
     int offset = -1;
     for (int i = 0; i < regionName.length; i++) {
       if (regionName[i] == DELIMITER) {
         offset = i;
         break;
       }
     }
     if(offset == -1) throw new IOException("Invalid regionName format");
     byte [] tableName = new byte[offset];
     System.arraycopy(regionName, 0, tableName, 0, offset);
     offset = -1;
     for (int i = regionName.length - 1; i > 0; i--) {
       if(regionName[i] == DELIMITER) {
         offset = i;
         break;
       }
     }
     if(offset == -1) throw new IOException("Invalid regionName format");
     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[regionName.length - offset - 1];
     System.arraycopy(regionName, offset + 1, id, 0,
         regionName.length - offset - 1);
     byte [][] elements = new byte[3][];
     elements[0] = tableName;
     elements[1] = startKey;
     elements[2] = id;
     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 this.regionNameStr;
     }

     // old format. regionNameStr doesn't have the region name.
     //
     //
     return this.regionNameStr + "." + this.getEncodedName();
   }

   /** @return the encoded region name */
   public synchronized String getEncodedName() {
     if (this.encodedName == NO_HASH) {
       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;
   }

   /**
    * 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 the tableDesc */
   public HTableDescriptor getTableDesc(){
     return tableDesc;
   }

   /**
    * @param newDesc new table descriptor to use
    */
   public void setTableDesc(HTableDescriptor newDesc) {
     this.tableDesc = newDesc;
   }

   /** @return true if this is the root region */
   public boolean isRootRegion() {
     return this.tableDesc.isRootRegion();
   }

   /** @return true if this is the meta table */
   public boolean isMetaTable() {
     return this.tableDesc.isMetaTable();
   }

   /** @return true if this region is a meta region */
   public boolean isMetaRegion() {
     return this.tableDesc.isMetaRegion();
   }

   /**
    * @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;
   }

   /**
    * @see java.lang.Object#toString()
    */
   @Override
   public String toString() {
     return "REGION => {" + HConstants.NAME + " => '" +
       this.regionNameStr +
       "', STARTKEY => '" +
       Bytes.toStringBinary(this.startKey) + "', ENDKEY => '" +
       Bytes.toStringBinary(this.endKey) +
       "', ENCODED => " + getEncodedName() + "," +
       (isOffline()? " OFFLINE => true,": "") +
       (isSplit()? " SPLIT => true,": "") +
       " TABLE => {" + this.tableDesc.toString() + "}";
   }

   /**
    * @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 */
   @Override
   public byte getVersion() {
     return VERSION;
   }

   //
   // Writable
   //

   @Override
   public void write(DataOutput out) throws IOException {
     super.write(out);
     Bytes.writeByteArray(out, endKey);
     out.writeBoolean(offLine);
     out.writeLong(regionId);
     Bytes.writeByteArray(out, regionName);
     out.writeBoolean(split);
     Bytes.writeByteArray(out, startKey);
     tableDesc.write(out);
     out.writeInt(hashCode);
   }

   @Override
   public void readFields(DataInput in) throws IOException {
     super.readFields(in);
     this.endKey = Bytes.readByteArray(in);
     this.offLine = in.readBoolean();
     this.regionId = in.readLong();
     this.regionName = Bytes.readByteArray(in);
     this.regionNameStr = Bytes.toStringBinary(this.regionName);
     this.split = in.readBoolean();
     this.startKey = Bytes.readByteArray(in);
     this.tableDesc.readFields(in);
     this.hashCode = in.readInt();
   }

   //
   // Comparable
   //

   public int compareTo(HRegionInfo o) {
     if (o == null) {
       return 1;
     }

     // Are regions of same table?
     int result = Bytes.compareTo(this.tableDesc.getName(), o.tableDesc.getName());
     if (result != 0) {
       return result;
     }

     // Compare start keys.
     result = Bytes.compareTo(this.startKey, o.startKey);
     if (result != 0) {
       return result;
     }

     // Compare end keys.
     return Bytes.compareTo(this.endKey, o.endKey);
   }

   /**
    * @return Comparator to use comparing {@link KeyValue}s.
    */
   public KVComparator getComparator() {
     return isRootRegion()? KeyValue.ROOT_COMPARATOR: isMetaRegion()?
       KeyValue.META_COMPARATOR: KeyValue.COMPARATOR;
   }
 }
	/**
	* Copyright 2007 The Apache Software Foundation
	*
	* 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.DataInput;
	import java.io.DataOutput;
	import java.io.IOException;
	import java.util.Arrays;

	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;
	import org.apache.hadoop.hbase.KeyValue.KVComparator;
	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.io.VersionedWritable;
	import org.apache.hadoop.io.WritableComparable;

	/**
	* HRegion information.
	* Contains HRegion id, start and end keys, a reference to this
	* HRegions' table descriptor, etc.
	*/
	public class HRegionInfo extends VersionedWritable implements WritableComparable<HRegionInfo>{
	private static final byte VERSION = 0;
	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:
	* <tablename>,,<startkey>,<regionIdTimestamp>.<encodedName>.
	* where,
	* <encodedName> is a hex version of the MD5 hash of
	* <tablename>,<startkey>,<regionIdTimestamp>
	*
	* The old region name format:
	* <tablename>,<startkey>,<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
	*
	* ROOT, the first 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;

	/**
	* 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. ROOT and first 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;
	}

	/**
	* Use logging.
	* @param encodedRegionName The encoded regionname.
	* @return <code>-ROOT-</code> if passed <code>70236052</code> or
	* <code>.META.</code> if passed </code>1028785192</code> else returns
	* <code>encodedRegionName</code>
	*/
	public static String prettyPrint(final String encodedRegionName) {
	if (encodedRegionName.equals("70236052")) {
	return encodedRegionName + "/-ROOT-";
	} else if (encodedRegionName.equals("1028785192")) {
	return encodedRegionName + "/.META.";
	}
	return encodedRegionName;
	}

	/** delimiter used between portions of a region name */
	public static final int DELIMITER = ',';

	/** HRegionInfo for root region */
	public static final HRegionInfo ROOT_REGIONINFO =
	new HRegionInfo(0L, HTableDescriptor.ROOT_TABLEDESC);

	/** HRegionInfo for first meta region */
	public static final HRegionInfo FIRST_META_REGIONINFO =
	new HRegionInfo(1L, HTableDescriptor.META_TABLEDESC);

	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 String regionNameStr = "";
	private boolean split = false;
	private byte [] startKey = HConstants.EMPTY_BYTE_ARRAY;
	protected HTableDescriptor tableDesc = null;
	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 volatile String encodedName = NO_HASH;
	private byte [] encodedNameAsBytes = null;

	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 ^= this.tableDesc.hashCode();
	this.hashCode = result;
	}

	/**
	* Private constructor used constructing HRegionInfo for the catalog root and
	* first meta regions
	*/
	private HRegionInfo(long regionId, HTableDescriptor tableDesc) {
	super();
	this.regionId = regionId;
	this.tableDesc = tableDesc;

	// Note: Root & First Meta regions names are still in old format
	this.regionName = createRegionName(tableDesc.getName(), null,
	regionId, false);
	this.regionNameStr = Bytes.toStringBinary(this.regionName);
	setHashCode();
	}

	/** Default constructor - creates empty object */
	public HRegionInfo() {
	super();
	this.tableDesc = new HTableDescriptor();
	}

	/**
	* Construct HRegionInfo with explicit parameters
	*
	* @param tableDesc the table descriptor
	* @param startKey first key in region
	* @param endKey end of key range
	* @throws IllegalArgumentException
	*/
	public HRegionInfo(final HTableDescriptor tableDesc, final byte [] startKey,
	final byte [] endKey)
	throws IllegalArgumentException {
	this(tableDesc, startKey, endKey, false);
	}

	/**
	* Construct HRegionInfo with explicit parameters
	*
	* @param tableDesc 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(HTableDescriptor tableDesc, final byte [] startKey,
	final byte [] endKey, final boolean split)
	throws IllegalArgumentException {
	this(tableDesc, startKey, endKey, split, System.currentTimeMillis());
	}

	/**
	* Construct HRegionInfo with explicit parameters
	*
	* @param tableDesc 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(HTableDescriptor tableDesc, final byte [] startKey,
	final byte [] endKey, final boolean split, final long regionid)
	throws IllegalArgumentException {
	super();
	if (tableDesc == null) {
	throw new IllegalArgumentException("tableDesc cannot be null");
	}
	this.offLine = false;
	this.regionId = regionid;
	this.regionName = createRegionName(tableDesc.getName(), startKey, regionId, true);
	this.regionNameStr = Bytes.toStringBinary(this.regionName);
	this.split = split;
	this.endKey = endKey == null? HConstants.EMPTY_END_ROW: endKey.clone();
	this.startKey = startKey == null?
	HConstants.EMPTY_START_ROW: startKey.clone();
	this.tableDesc = tableDesc;
	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.regionNameStr = Bytes.toStringBinary(this.regionName);
	this.split = other.isSplit();
	this.startKey = other.getStartKey();
	this.tableDesc = other.getTableDesc();
	this.hashCode = other.hashCode();
	this.encodedName = other.getEncodedName();
	}

	/**
	* 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 byte [] 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 byte [] 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 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 byte [] tableName,
	final byte [] startKey, final byte [] id, boolean newFormat) {
	byte [] b = new byte [tableName.length + 2 + id.length +
	(startKey == null? 0: startKey.length) +
	(newFormat ? (MD5_HEX_LENGTH + 2) : 0)];

	int offset = tableName.length;
	System.arraycopy(tableName, 0, b, 0, offset);
	b[offset++] = DELIMITER;
	if (startKey != null && startKey.length > 0) {
	System.arraycopy(startKey, 0, b, offset, startKey.length);
	offset += startKey.length;
	}
	b[offset++] = DELIMITER;
	System.arraycopy(id, 0, b, offset, id.length);
	offset += id.length;

	if (newFormat) {
	//
	// Encoded name should be built into the region name.
	//
	// Use the region name thus far (namely, <tablename>,<startKey>,<id>)
	// 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.
	*/
	public static byte [] getTableName(byte [] regionName) {
	int offset = -1;
	for (int i = 0; i < regionName.length; i++) {
	if (regionName[i] == DELIMITER) {
	offset = i;
	break;
	}
	}
	byte [] tableName = new byte[offset];
	System.arraycopy(regionName, 0, tableName, 0, offset);
	return tableName;
	}

	/**
	* 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 {
	int offset = -1;
	for (int i = 0; i < regionName.length; i++) {
	if (regionName[i] == DELIMITER) {
	offset = i;
	break;
	}
	}
	if(offset == -1) throw new IOException("Invalid regionName format");
	byte [] tableName = new byte[offset];
	System.arraycopy(regionName, 0, tableName, 0, offset);
	offset = -1;
	for (int i = regionName.length - 1; i > 0; i--) {
	if(regionName[i] == DELIMITER) {
	offset = i;
	break;
	}
	}
	if(offset == -1) throw new IOException("Invalid regionName format");
	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[regionName.length - offset - 1];
	System.arraycopy(regionName, offset + 1, id, 0,
	regionName.length - offset - 1);
	byte [][] elements = new byte[3][];
	elements[0] = tableName;
	elements[1] = startKey;
	elements[2] = id;
	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 this.regionNameStr;
	}

	// old format. regionNameStr doesn't have the region name.
	//
	//
	return this.regionNameStr + "." + this.getEncodedName();
	}

	/** @return the encoded region name */
	public synchronized String getEncodedName() {
	if (this.encodedName == NO_HASH) {
	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;
	}

	/**
	* 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 the tableDesc */
	public HTableDescriptor getTableDesc(){
	return tableDesc;
	}

	/**
	* @param newDesc new table descriptor to use
	*/
	public void setTableDesc(HTableDescriptor newDesc) {
	this.tableDesc = newDesc;
	}

	/** @return true if this is the root region */
	public boolean isRootRegion() {
	return this.tableDesc.isRootRegion();
	}

	/** @return true if this is the meta table */
	public boolean isMetaTable() {
	return this.tableDesc.isMetaTable();
	}

	/** @return true if this region is a meta region */
	public boolean isMetaRegion() {
	return this.tableDesc.isMetaRegion();
	}

	/**
	* @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;
	}

	/**
	* @see java.lang.Object#toString()
	*/
	@Override
	public String toString() {
	return "REGION => {" + HConstants.NAME + " => '" +
	this.regionNameStr +
	"', STARTKEY => '" +
	Bytes.toStringBinary(this.startKey) + "', ENDKEY => '" +
	Bytes.toStringBinary(this.endKey) +
	"', ENCODED => " + getEncodedName() + "," +
	(isOffline()? " OFFLINE => true,": "") +
	(isSplit()? " SPLIT => true,": "") +
	" TABLE => {" + this.tableDesc.toString() + "}";
	}

	/**
	* @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 */
	@Override
	public byte getVersion() {
	return VERSION;
	}

	//
	// Writable
	//

	@Override
	public void write(DataOutput out) throws IOException {
	super.write(out);
	Bytes.writeByteArray(out, endKey);
	out.writeBoolean(offLine);
	out.writeLong(regionId);
	Bytes.writeByteArray(out, regionName);
	out.writeBoolean(split);
	Bytes.writeByteArray(out, startKey);
	tableDesc.write(out);
	out.writeInt(hashCode);
	}

	@Override
	public void readFields(DataInput in) throws IOException {
	super.readFields(in);
	this.endKey = Bytes.readByteArray(in);
	this.offLine = in.readBoolean();
	this.regionId = in.readLong();
	this.regionName = Bytes.readByteArray(in);
	this.regionNameStr = Bytes.toStringBinary(this.regionName);
	this.split = in.readBoolean();
	this.startKey = Bytes.readByteArray(in);
	this.tableDesc.readFields(in);
	this.hashCode = in.readInt();
	}

	//
	// Comparable
	//

	public int compareTo(HRegionInfo o) {
	if (o == null) {
	return 1;
	}

	// Are regions of same table?
	int result = Bytes.compareTo(this.tableDesc.getName(), o.tableDesc.getName());
	if (result != 0) {
	return result;
	}

	// Compare start keys.
	result = Bytes.compareTo(this.startKey, o.startKey);
	if (result != 0) {
	return result;
	}

	// Compare end keys.
	return Bytes.compareTo(this.endKey, o.endKey);
	}

	/**
	* @return Comparator to use comparing {@link KeyValue}s.
	*/
	public KVComparator getComparator() {
	return isRootRegion()? KeyValue.ROOT_COMPARATOR: isMetaRegion()?
	KeyValue.META_COMPARATOR: KeyValue.COMPARATOR;
	}
	}