org.apache.hadoop.hbase
Class HBaseAdmin

java.lang.Object
  org.apache.hadoop.hbase.HBaseAdmin

All Implemented Interfaces:

HConstants

public class HBaseAdmin
extends Object
implements HConstants

Provides administrative functions for HBase

Field Summary

protected HConnection	connection
protected org.apache.commons.logging.Log	LOG
protected HMasterInterface	master
protected int	numRetries
protected long	pause

Fields inherited from interface org.apache.hadoop.hbase.HConstants

ALL_VERSIONS, COL_REGIONINFO, COL_REGIONINFO_ARRAY, COL_SERVER, COL_SPLITA, COL_SPLITB, COL_STARTCODE, COLUMN_FAMILY, COLUMN_FAMILY_ARRAY, COLUMN_FAMILY_STR, DEFAULT_HBASE_DIR, DEFAULT_HOST, DEFAULT_MASTER_ADDRESS, DEFAULT_MASTER_INFOPORT, DEFAULT_MAX_FILE_SIZE, DEFAULT_REGION_SERVER_CLASS, DEFAULT_REGIONSERVER_ADDRESS, DEFAULT_REGIONSERVER_INFOPORT, EMPTY_START_ROW, EMPTY_TEXT, HBASE_DIR, HREGION_LOGDIR_NAME, HREGION_OLDLOGFILE_NAME, HREGIONDIR_PREFIX, LATEST_TIMESTAMP, MASTER_ADDRESS, META_TABLE_NAME, REGION_SERVER_CLASS, REGIONSERVER_ADDRESS, ROOT_TABLE_NAME, THREAD_WAKE_FREQUENCY, UTF8_ENCODING

Constructor Summary

HBaseAdmin(Configuration conf)
Constructor

Method Summary

void	addColumn(Text tableName, HColumnDescriptor column) Add a column to an existing table
protected void	checkReservedTableName(Text tableName)
void	createTable(HTableDescriptor desc) Creates a new table
void	createTableAsync(HTableDescriptor desc) Creates a new table but does not block and wait for it to come online.
void	deleteColumn(Text tableName, Text columnName) Delete a column from a table
void	deleteTable(Text tableName) Deletes a table
void	disableTable(Text tableName) Disables a table (takes it off-line) If it is being served, the master will tell the servers to stop serving it.
void	enableTable(Text tableName) Brings a table on-line (enables it)
HMasterInterface	getMaster()
boolean	isMasterRunning()
HTableDescriptor[]	listTables() List all the userspace tables.
void	shutdown() Shuts down the HBase instance
boolean	tableExists(Text tableName)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOG

protected final org.apache.commons.logging.Log LOG

connection

protected final HConnection connection

pause

protected final long pause

numRetries

protected final int numRetries

master

protected volatile HMasterInterface master

Constructor Detail

HBaseAdmin

public HBaseAdmin(Configuration conf)
           throws MasterNotRunningException

Constructor

Parameters:

conf - Configuration object

Throws:

MasterNotRunningException

Method Detail

getMaster

public HMasterInterface getMaster()
                           throws MasterNotRunningException

Returns:

proxy connection to master server for this instance

Throws:

MasterNotRunningException

isMasterRunning

public boolean isMasterRunning()

Returns:

- true if the master server is running

tableExists

public boolean tableExists(Text tableName)
                    throws MasterNotRunningException

Parameters:

tableName - Table to check.

Returns:

True if table exists already.

Throws:

MasterNotRunningException

listTables

public HTableDescriptor[] listTables()
                              throws IOException

List all the userspace tables. In other words, scan the META table. If we wanted this to be really fast, we could implement a special catalog table that just contains table names and their descriptors. Right now, it only exists as part of the META table's region info.

Returns:

- returns an array of HTableDescriptors

Throws:

IOException

createTable

public void createTable(HTableDescriptor desc)
                 throws IOException

Creates a new table

Parameters:

desc - table descriptor for table

Throws:

IllegalArgumentException - if the table name is reserved

MasterNotRunningException - if master is not running

NoServerForRegionException - if root region is not being served

TableExistsException - if table already exists (If concurrent threads, the table may have been created between test-for-existence and attempt-at-creation).

IOException

createTableAsync

public void createTableAsync(HTableDescriptor desc)
                      throws IOException

Creates a new table but does not block and wait for it to come online.

Parameters:

desc - table descriptor for table

Throws:

IllegalArgumentException - if the table name is reserved

MasterNotRunningException - if master is not running

NoServerForRegionException - if root region is not being served

TableExistsException - if table already exists (If concurrent threads, the table may have been created between test-for-existence and attempt-at-creation).

IOException

deleteTable

public void deleteTable(Text tableName)
                 throws IOException

Deletes a table

Parameters:

tableName - name of table to delete

Throws:

IOException

enableTable

public void enableTable(Text tableName)
                 throws IOException

Brings a table on-line (enables it)

Parameters:

tableName - name of the table

Throws:

IOException

disableTable

public void disableTable(Text tableName)
                  throws IOException

Disables a table (takes it off-line) If it is being served, the master will tell the servers to stop serving it.

Parameters:

tableName - name of table

Throws:

IOException

addColumn

public void addColumn(Text tableName,
                      HColumnDescriptor column)
               throws IOException

Add a column to an existing table

Parameters:

tableName - name of the table to add column to

column - column descriptor of column to be added

Throws:

IOException

deleteColumn

public void deleteColumn(Text tableName,
                         Text columnName)
                  throws IOException

Delete a column from a table

Parameters:

tableName - name of table

columnName - name of column to be deleted

Throws:

IOException

shutdown

public void shutdown()
              throws IOException

Shuts down the HBase instance

Throws:

IOException

checkReservedTableName

protected void checkReservedTableName(Text tableName)