org.apache.hadoop.hbase.client

Class ReversedScannerCallable

java.lang.Object

org.apache.hadoop.hbase.client.RegionServerCallable<Result[]>

org.apache.hadoop.hbase.client.ScannerCallable

org.apache.hadoop.hbase.client.ReversedScannerCallable

All Implemented Interfaces:

Callable<Result[]>, RetryingCallable<Result[]>

@InterfaceAudience.Public
@InterfaceStability.Evolving
public class ReversedScannerCallable
extends ScannerCallable

A reversed ScannerCallable which supports backward scanning.

Field Summary

Fields

Modifier and Type	Field and Description
protected byte[]	locateStartRow The start row for locating regions.

Fields inherited from class org.apache.hadoop.hbase.client.ScannerCallable

controller, instantiated, isRegionServerRemote, LOG, LOG_SCANNER_ACTIVITY, LOG_SCANNER_LATENCY_CUTOFF, scanMetrics

Fields inherited from class org.apache.hadoop.hbase.client.RegionServerCallable

connection, location, MIN_WAIT_DEAD_SERVER, row, tableName

Constructor Summary

Constructors

Constructor and Description
ReversedScannerCallable(HConnection connection, TableName tableName, Scan scan, ScanMetrics scanMetrics, byte[] locateStartRow) Deprecated.
ReversedScannerCallable(HConnection connection, TableName tableName, Scan scan, ScanMetrics scanMetrics, byte[] locateStartRow, PayloadCarryingRpcController rpcFactory)

Method Summary

Methods

Modifier and Type	Method and Description
void	prepare(boolean reload) Prepare for connection to the server hosting region with row from tablename.

Methods inherited from class org.apache.hadoop.hbase.client.ScannerCallable

call, checkIfRegionServerIsRemote, getCaching, getHRegionInfo, getScan, openScanner, setCaching, setClose

Methods inherited from class org.apache.hadoop.hbase.client.RegionServerCallable

getExceptionMessageAdditionalDetail, getLocation, getRow, getStub, getTableName, setLocation, sleep, throwable

Methods inherited from class java.lang.Object

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

Field Detail

locateStartRow

protected final byte[] locateStartRow

The start row for locating regions. In reversed scanner, may locate the regions for a range of keys when doing ReversedClientScanner.nextScanner(int, boolean)

Constructor Detail

ReversedScannerCallable

@Deprecated
public ReversedScannerCallable(HConnection connection,
                                  TableName tableName,
                                  Scan scan,
                                  ScanMetrics scanMetrics,
                                  byte[] locateStartRow)

Deprecated.

ReversedScannerCallable

public ReversedScannerCallable(HConnection connection,
                       TableName tableName,
                       Scan scan,
                       ScanMetrics scanMetrics,
                       byte[] locateStartRow,
                       PayloadCarryingRpcController rpcFactory)

Parameters:

connection -

tableName -

scan -

scanMetrics -

locateStartRow - The start row for locating regions

rpcFactory -

Method Detail

prepare

public void prepare(boolean reload)
             throws IOException

Description copied from class: RegionServerCallable

Prepare for connection to the server hosting region with row from tablename. Does lookup to find region location and hosting server.

Specified by:

prepare in interface RetryingCallable<Result[]>

Overrides:

prepare in class ScannerCallable

Parameters:

reload - force reload of server location

Throws:

IOException