org.apache.hadoop.hbase.client

Interface RegionLocator

All Superinterfaces:

AutoCloseable, Closeable

All Known Implementing Classes:

HRegionLocator

@InterfaceAudience.Public
public interface RegionLocator
extends Closeable

Used to view region location information for a single HBase table. Obtain an instance from an Connection.

Since:

0.99.0

See Also:

ConnectionFactory, Connection, Table

Field Summary

Fields

Modifier and Type	Field and Description
static String	LOCATOR_META_REPLICAS_MODE Configuration for Region Locator's mode when meta replica is configured.
static String	LOCATOR_META_REPLICAS_MODE_LOADBALANCE_SELECTOR Configuration for meta replica selector when Region Locator's LoadBalance mode is configured.

Method Summary

Modifier and Type	Method and Description
void	clearRegionLocationCache() Clear all the entries in the region location cache.
List<HRegionLocation>	getAllRegionLocations() Retrieves all of the regions associated with this table.
default byte[][]	getEndKeys() Gets the ending row key for every region in the currently open table.
TableName	getName() Gets the fully qualified table name instance of this table.
default HRegionLocation	getRegionLocation(byte[] row) Finds the region on which the given row is being served.
default HRegionLocation	getRegionLocation(byte[] row, boolean reload) Finds the region on which the given row is being served.
default HRegionLocation	getRegionLocation(byte[] row, int replicaId) Finds the region with the given replica id on which the given row is being served.
HRegionLocation	getRegionLocation(byte[] row, int replicaId, boolean reload) Finds the region with the given replica id on which the given row is being served.
default List<HRegionLocation>	getRegionLocations(byte[] row) Find all the replicas for the region on which the given row is being served.
List<HRegionLocation>	getRegionLocations(byte[] row, boolean reload) Find all the replicas for the region on which the given row is being served.
default Pair<byte[][],byte[][]>	getStartEndKeys() Gets the starting and ending row keys for every region in the currently open table.
default byte[][]	getStartKeys() Gets the starting row key for every region in the currently open table.

Methods inherited from interface java.io.Closeable

close

Field Detail

LOCATOR_META_REPLICAS_MODE

static final String LOCATOR_META_REPLICAS_MODE

Configuration for Region Locator's mode when meta replica is configured. Valid values are: HedgedRead, LoadBalance, None

See Also:

Constant Field Values

LOCATOR_META_REPLICAS_MODE_LOADBALANCE_SELECTOR

static final String LOCATOR_META_REPLICAS_MODE_LOADBALANCE_SELECTOR

Configuration for meta replica selector when Region Locator's LoadBalance mode is configured. The default value is org.apache.hadoop.hbase.client.CatalogReplicaLoadBalanceSimpleSelector.

See Also:

Constant Field Values

Method Detail

getRegionLocation

default HRegionLocation getRegionLocation(byte[] row)
                                   throws IOException

Finds the region on which the given row is being served. Does not reload the cache.

Parameters:

row - Row to find.

Returns:

Location of the row.

Throws:

IOException - if a remote or network exception occurs

getRegionLocation

default HRegionLocation getRegionLocation(byte[] row,
                                          boolean reload)
                                   throws IOException

Finds the region on which the given row is being served.

Parameters:

row - Row to find.

reload - true to reload information or false to use cached information

Returns:

Location of the row.

Throws:

IOException - if a remote or network exception occurs

getRegionLocation

default HRegionLocation getRegionLocation(byte[] row,
                                          int replicaId)
                                   throws IOException

Finds the region with the given replica id on which the given row is being served.

Parameters:

row - Row to find.

replicaId - the replica id

Returns:

Location of the row.

Throws:

IOException - if a remote or network exception occurs

getRegionLocation

HRegionLocation getRegionLocation(byte[] row,
                                  int replicaId,
                                  boolean reload)
                           throws IOException

Finds the region with the given replica id on which the given row is being served.

Parameters:

row - Row to find.

replicaId - the replica id

reload - true to reload information or false to use cached information

Returns:

Location of the row.

Throws:

IOException - if a remote or network exception occurs

getRegionLocations

default List<HRegionLocation> getRegionLocations(byte[] row)
                                          throws IOException

Find all the replicas for the region on which the given row is being served.

Parameters:

row - Row to find.

Returns:

Locations for all the replicas of the row.

Throws:

IOException - if a remote or network exception occurs

getRegionLocations

List<HRegionLocation> getRegionLocations(byte[] row,
                                         boolean reload)
                                  throws IOException

Find all the replicas for the region on which the given row is being served.

Parameters:

row - Row to find.

reload - true to reload information or false to use cached information

Returns:

Locations for all the replicas of the row.

Throws:

IOException - if a remote or network exception occurs

clearRegionLocationCache

void clearRegionLocationCache()

Clear all the entries in the region location cache.

This may cause performance issue so use it with caution.

getAllRegionLocations

List<HRegionLocation> getAllRegionLocations()
                                     throws IOException

Retrieves all of the regions associated with this table.

Usually we will go to meta table directly in this method so there is no reload parameter.

Notice that the location for region replicas other than the default replica are also returned.

Returns:

a List of all regions associated with this table.

Throws:

IOException - if a remote or network exception occurs

getStartKeys

default byte[][] getStartKeys()
                       throws IOException

Gets the starting row key for every region in the currently open table.

This is mainly useful for the MapReduce integration.

Returns:

Array of region starting row keys

Throws:

IOException - if a remote or network exception occurs

getEndKeys

default byte[][] getEndKeys()
                     throws IOException

Gets the ending row key for every region in the currently open table.

This is mainly useful for the MapReduce integration.

Returns:

Array of region ending row keys

Throws:

IOException - if a remote or network exception occurs

getStartEndKeys

default Pair<byte[][],byte[][]> getStartEndKeys()
                                         throws IOException

Gets the starting and ending row keys for every region in the currently open table.

This is mainly useful for the MapReduce integration.

Returns:

Pair of arrays of region starting and ending row keys

Throws:

IOException - if a remote or network exception occurs

getName

TableName getName()

Gets the fully qualified table name instance of this table.