Newly Added or Modified APIs

• org.apache.hadoop.hbase.Cell of HBase 0.98.3 rather than org.apache.hadoop.hbase.KeyValue of HBase 0.94 is recommended as the key-value data object.
• It is recommended that HConnection connection = HConnectionManager.createConnection(conf) be used to create a connection pool in HBase 0.98.3. The HTablePool is abandoned.
• For details about the new EndPoint API, visit http://hbase.apache.org/book/cp.html.
• The isReversed() and setReversed(boolean reversed) reversed scan methods are added to org.apache.hadoop.hbase.client.Scan.
• For details about API changes from HBase 0.98 to HBase 1.0, visit https://issues.apache.org/jira/browse/hbase-10602.
• org.apache.hadoop.hbase.mapreduce rather than org.apache.hadoop.hbase.mapred is recommended for HBase 1.0.
• For details about the version, visit https://blogs.apache.org/hbase/entry/start_of_a_new_era.
• New APIs added to obtain HBase replication metrics

  Table 1 org.apache.hadoop.hbase.client.replication.ReplicationAdmin

  Method	Description
  getSourceMetricsSummary(String id)	Parameter type: String The source metric summary of the peer ID needs to be obtained. Return type: Map<String, String> Returned: A map, where the key is the RegionServer name and the value is the source cluster metric summary of the specified peer ID. Summary metrics are sizeOfLogToReplicate and timeForLogToReplicate.
  getSourceMetrics(String id)	Parameter type: String The source metric summary of the peer ID needs to be obtained. Return type: Map<String, String> Returned: A map, where the key is the RegionServer name and the value is the source cluster metric of the specified peer ID.
  getSinkMetrics()	Return type: Map<String, String> Returned: A map, where the key is the RegionServer name and the value is the source cluster sink metric of the specified peer ID.
  getPeerSinkMetrics(String id)	Parameter type: String The source metric summary of the peer ID needs to be obtained. Return type: Map<String, String> Returned: A map, where the key is the RegionServer name and the value is the source cluster sink metric of the specified peer ID.

  

  All methods return a Map, where the key is "RegionServer name (IP/Host)" and the value is the string containing all the metrics in format of 'Metric Name'='Metric Value' [, 'Metric Name'= 'Metric Value']*.

  Example: SizeOfHFileRefsQueue=0, AgeOfLastShippedOp=0

  Table 2 org.apache.hadoop.hbase.replication.ReplicationLoadSource

  Method	Description
  getPeerID()	Return type: String Returned: peer cluster ID
  getAgeOfLastShippedOp()	Return type: long Returned: milliseconds that the last successful replication request lasts
  getSizeOfLogQueue()	Return type: long Returned: write-ahead logs (WALs) waiting for replication in the queue
  getTimeStampOfLastShippedOp()	Return type: long Returned: timestamp of the last successful replication request
  getReplicationLag()	Return type: long Returned: interval between current time and the time of the last successful replication request
  getShippedOps()	Return type: long Returned: total number of data ops transferred
  getShippedBytes()	Return type: long Returned: total number of data bytes transferred
  getShippedBatches()	Return type: long Returned: total number of data batches transferred
  getLogReadInBytes()	Return type: long Returned: total number of bytes read from WAL
  getLogEditsRead()	Return type: long Returned: total number of edits read from WAL
  getSizeOfLogToReplicate()	Return type: long Returned: total size of WALs waiting to be replicated in the queue
  getTimeForLogToReplicate()	Return type: long Returned: seconds spent in replicating WALs in the queue
  getShippedHFiles()	Return type: long Returned: total number of HFiles transferred
  getSizeOfHFileRefsQueue()	Return type: long Returned: total number of HFiles waiting to be replicated
  getLogEditsFiltered()	Return type: long Returned: total number of WAL edits filtered
  getFailedReplicationAttempts()	Return type: long Returned: times failed to replicate data for a single request

  Table 3 org.apache.hadoop.hbase.replication.ReplicationLoadSink

  Method	Description
  getAgeOfLastAppliedOp()	Return type: long Returned: milliseconds that the last successful applied WAL edits last
  getTimeStampsOfLastAppliedOp()	Return type: long Returned: timestamp of the last successful applied WAL edit
  getAppliedBatches()	Return type: long Returned: total number of data batches applied
  getAppliedOps()	Return type: long Returned: total number of data ops applied
  getAppliedHFiles()	Return type: long Returned: total number of HFiles applied

  

  The new API OF Replication Admin obtains the metric values from HMaster. Each RegionServer reports status to HMaster at every heartbeat interval, which is 3 seconds by default. Therefore, this API reports the latest metric value at the last heartbeat by using the RegionServer.

  If you need the latest metric value, use the JMX API provided by the RegionServer.

• 1.3.1 (MRS 1.6) API Changes

  Table 4 API removed from org.apache.hadoop.hbase.client.Admin

  Method	Description
  compactMob()	Return type: void

  ACL client APIs are enhanced to query the permissions based on the namespace, table name, column family, and column qualifier of a specific user. The client can also validate whether the specified user has permissions to perform operations on the mentioned table, column family, or column qualifier.

  Table 5 org.apache.hadoop.hbase.security.access.AccessControlClient

  Method	Description
  getUserPermissions(Connection connection, String tableRegex, String userName)	Parameter type: Connection HBase cluster connection Parameter type: String Table name pattern, based on the permissions to be retrieved. If the value of tableRegex is null, the global permission is used. If the value of tableRegex contains @, the namespace permission is used. Otherwise, the table permission will be retrieved. tableRegex can be a regular expression of a table or namespace. Parameter type: String Name of the user whose permissions will be filtered. If username is left blank, all user permissions will be retrieved. Return type: List<UserPermission> Returned: List of user permissions
  getUserPermissions(Connection connection, String tableRegex, byte[] columnFamily)	Parameter type: Connection HBase cluster connection Parameter type: String Table name pattern, based on the permissions to be retrieved. The table name cannot be null, empty, or a namespace name. Parameter type: byte[] Column family, based on the permissions to be retrieved. If columnFamily is left blank, all column family permissions will be retrieved. Return type: List<UserPermission> Returned: List of user permissions
  getUserPermissions(Connection connection, String tableRegex, byte[] columnFamily, String userName)	Parameter type: Connection HBase cluster connection Parameter type: String Table name pattern, based on the permissions to be retrieved. The table name cannot be null, empty, or a namespace name. Parameter type: byte[] Column family, based on the permissions to be retrieved. If columnFamily is left blank, all column family permissions will be retrieved. Parameter type: String Name of the user whose permissions will be filtered. If username is left blank, all user permissions will be retrieved. Return type: List<UserPermission> Returned: List of user permissions
  getUserPermissions(Connection connection, String tableRegex, byte[] columnFamily, byte[] columnQualifier)	Parameter type: Connection HBase cluster connection Parameter type: String Table name pattern, based on the permissions to be retrieved. The table name cannot be null, empty, or a namespace name. Parameter type: byte[] Column family, based on the permissions to be retrieved. If columnFamily is left blank, all column family permissions will be retrieved. Parameter type: byte[] Column qualifier, based on the permissions to be retrieved. If columnQualifier is left blank, all column qualifier permissions will be retrieved. Return type: List<UserPermission> Returned: List of user permissions
  getUserPermissions(Connection connection, String tableRegex, byte[] columnFamily, byte[] columnQualifier, String userName)	Parameter type: Connection HBase cluster connection Parameter type: String Table name pattern, based on the permissions to be retrieved. The table name cannot be null, empty, or a namespace name. Parameter type: byte[] Column family, based on the permissions to be retrieved. If columnFamily is left blank, all column family permissions will be retrieved. Parameter type: byte[] Column qualifier, based on the permissions to be retrieved. If columnQualifier is left blank, all column qualifier permissions will be retrieved. Parameter type: String Name of the user whose permissions will be filtered. If username is left blank, all user permissions will be retrieved. Return type: List<UserPermission> Returned: List of user permissions
  hasPermission(Connection connection, String tableName, String columnFamily, String columnQualifier, String userName, Permission.Action... actions)	Verify whether the specified user has permissions to perform operations on the mentioned table, column family, or column qualifier. Parameter type: Connection HBase cluster connection Parameter type: String Table name. The table name cannot be null or empty. Parameter type: String Column family. If columnFamily is left blank, the verification is performed for tables. Parameter type: String Column qualifier. If columnQualifier is left blank, the verification is performed for tables and column families. If columnFamily is transferred as null or empty, the value of columnQualifier will not be considered. Parameter type: String Name of the user whose permissions will be filtered. If username is left blank, all user permissions will be retrieved. Parameter type: Permission.Action Actions that the specified user wants to perform on the table, column family, or column qualifier
  hasPermission(Connection connection, String tableName, byte[] columnFamily, byte[] columnQualifier, String userName, Permission.Action... actions)	Verify whether the specified user has permissions to perform operations on the mentioned table, column family, or column qualifier. Parameter type: Connection HBase cluster connection Parameter type: String Table name. The table name cannot be null or empty. Parameter type: byte[] Column family. If columnFamily is left blank, the verification is performed for tables. Parameter type: byte[] Column qualifier. If columnQualifier is left blank, the verification is performed for tables and column families. If columnFamily is transferred as null or empty, the value of columnQualifier will not be considered. Parameter type: String Name of the user whose permissions will be filtered. If username is left blank, all user permissions will be retrieved. Parameter type: Action Actions that the specified user wants to perform on the table, column family, or column qualifier

• 1.3.1 (MRS 1.7) API Changes
  • Added HIndex API

  Table 6 org.apache.hadoop.hbase.hindex.client.HIndexAdmin

  Method	Description
  addIndices(TableName tablename,TableIndices tableIndices)	Parameter: TableName Name of the table to which the user wants to add a specified index. Parameter: TableIndices Table index to be added to the table Return type: void
  addIndicesWithData(TableName tablename,TableIndices tableIndices)	Parameter: TableName Name of the table to which the user wants to add a specified index Parameter: TableIndices Table index to be added to the table Return type: void
  dropIndices(TableName tableName,List <String> list)	Parameter: TableName Name of the table from which the user wants to delete an index Parameter: List<String> Contains the list of indexes to be deleted. Return type: void
  dropIndicesWithData(TableName tableName,List <String> list)	Parameter: TableName Name of the table from which the user wants to delete a specified index Parameter: List<String> Contains the list of indexes to be deleted. Return type: void
  disableIndices(TableName tableName,List <String> list)	Parameter: TableName Name of the table for which the user wants to disable a specified index Parameter: List<String> Contains the list of indexes to be disabled. Return type: void
  enableIndices(TableName tableName,List <String> list)	Parameter: TableName Name of the table for which the user wants to enable a specified index Parameter: List<String> Contains the list of indexes to be enabled. Return type: void
  listIndices(TableName tableName)	Parameter: TableName Name of the table for which the user wants to list all indexes Return type: List <Pair <HIndexSpecification,IndexState >> Return: A secondary index list is returned. The first element is the index specification, and the second element is the current state of the index.

• 2.1.1 (MRS 2.x) API Changes
  Removed APIs

  Table 7 APIs removed from org.apache.hadoop.hbase.client.Admin

  Method	Description
  compactMob(final TableName tableName)	Return type: void Parameter type: TableName
  compactMob(final TableName tableName, final byte[] columnFamily)	Return type: void Parameter type: TableName, byte[]
  majorCompactMob ( org.apache.hadoop.hbase.TableName tableName )	Return type: void Parameter type: TableName
  majorCompactMob ( org.apache.hadoop.hbase.TableName tableName, byte[ ] columnFamily)	Return type: void Parameter type: TableName, byte[]
  isAclEnable ( )	Return type: boolean
  isNamespaceAvailable ( String nameOfNamespace )	Return type: boolean
  multiSplit ( byte[ ] regionName, byte[ ][ ] splitKeys)	Return type: void
  multiSplitSync ( byte[ ] regionName, byte[ ][ ] splitKeys)	Return type: void

  Table 8 APIs removed from org.apache.hadoop.hbase.client.Put

  Method	Description
  add ( byte[ ] family, byte[ ] qualifier, byte[ ] value )	Return type: Put Parameter type: byte[]
  add ( byte[ ] family, byte[ ] qualifier, long ts, byte[ ] value )	Return type: Put Parameter type: byte[]
  add ( byte[ ] family, java.nio.ByteBuffer qualifier, long ts, java.nio.ByteBuffer value )	Return type: Put Parameter type: byte[]
  setWriteToWAL ( boolean write )	Return type: Put Parameter type: boolean

  Table 9 APIs removed from org.apache.hadoop.hbase.security.token.TokenUtil

  Method	Description
  obtainToken ( org.apache.hadoop.conf.Configuration conf )	Return type: Token<AuthenticationTokenIdentifier> Parameter type: Configuration

  Added APIs

  Table 10 APIs added to org.apache.hadoop.hbase.client.Admin

  Method	Description
  decommissionRegionServers ( java.util.List<org.apache.hadoop.hbase.ServerName> servers, boolean offload)	Return type: void Parameter type: List<ServerName>, boolean Mark the RegionServer in the list as the decommissioned state. If offload is set to true, the regions of the RegionServer are allocated to other RegionServers. If offload is set to false, the regions of the current RegionServer are not re-allocated, and no new region is allocated to the RegionServer.
  listDecommissionedRegionServers ( )	Return type: List<ServerName> The decommissioned RegionServers in the current cluster are listed.
  recommissionRegionServer ( org.apache.hadoop.hbase.ServerName server, java.util.List<byte[ ]> encodedRegionNames)	Return type: void Parameter type: ServerName, byte[] Recommission the imported decommissioned RegionServers.

  

  • Currently, only the changes of common APIs for client operations in MRS 2.x compared with earlier version are listed.
  • APIs used by HBase are the same as APIs of Apache HBase. For details about how to use the APIs, see http://hbase.apache.org/apidocs/index.html.
  • MRS 2.x is consistent with Apache HBase 2.x. For details about the changes, see http://hbase.apache.org/book.html#_changes_of_note.