org.apache.hadoop.hbase.client

Class ReversedScannerCallable

java.lang.Object

org.apache.hadoop.hbase.client.RegionServerCallable<T,org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.ClientService.BlockingInterface>

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

org.apache.hadoop.hbase.client.ScannerCallable

org.apache.hadoop.hbase.client.ReversedScannerCallable

All Implemented Interfaces:

RetryingCallable<Result[]>

@InterfaceAudience.Private
public class ReversedScannerCallable
extends ScannerCallable

A reversed ScannerCallable which supports backward scanning.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.client.ScannerCallable

ScannerCallable.MoreResults

Field Summary

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

closed, cursor, heartbeatMessage, id, instantiated, isRegionServerRemote, LOG, LOG_SCANNER_ACTIVITY, LOG_SCANNER_LATENCY_CUTOFF, renew, rpcControllerFactory, scan, scanMetrics, scannerId

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

location, rpcController, stub

Constructor Summary

Constructors

Constructor and Description
ReversedScannerCallable(ClusterConnection connection, TableName tableName, Scan scan, ScanMetrics scanMetrics, RpcControllerFactory rpcFactory)
ReversedScannerCallable(ClusterConnection connection, TableName tableName, Scan scan, ScanMetrics scanMetrics, RpcControllerFactory rpcFactory, int replicaId)

Method Summary

Modifier and Type	Method and Description
ScannerCallable	getScannerCallableForReplica(int id)
private List<HRegionLocation>	locateRegionsInRange(byte[] startKey, byte[] endKey, boolean reload) Get the corresponding regions for an arbitrary range of keys.
void	prepare(boolean reload) Prepare by setting up any connections to servers, etc., ahead of call invocation.

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

checkIfRegionServerIsRemote, getCaching, getCursor, getHRegionInfo, getScan, isHeartbeatMessage, moreResultsForScan, moreResultsInRegion, rpcCall, setCaching, setClose, setMoreResultsForScan, setMoreResultsInRegion, setRenew

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

doGet, doMutate, setStubByServiceName

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

call, getConnection, getExceptionMessageAdditionalDetail, getLocation, getPriority, getRow, getRpcController, getRpcControllerCellScanner, getStub, getTableName, setLocation, setRpcControllerCellScanner, setStub, sleep, throwable

Methods inherited from class java.lang.Object

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

Constructor Detail

ReversedScannerCallable

public ReversedScannerCallable(ClusterConnection connection,
                               TableName tableName,
                               Scan scan,
                               ScanMetrics scanMetrics,
                               RpcControllerFactory rpcFactory)

Parameters:

connection -

tableName -

scan -

scanMetrics -

rpcFactory - to create an RpcController to talk to the regionserver

ReversedScannerCallable

public ReversedScannerCallable(ClusterConnection connection,
                               TableName tableName,
                               Scan scan,
                               ScanMetrics scanMetrics,
                               RpcControllerFactory rpcFactory,
                               int replicaId)

Parameters:

connection -

tableName -

scan -

scanMetrics -

rpcFactory - to create an RpcController to talk to the regionserver

replicaId - the replica id

Method Detail

prepare

public void prepare(boolean reload)
             throws IOException

Description copied from interface: RetryingCallable

Prepare by setting up any connections to servers, etc., ahead of call invocation. TODO: We call prepare before EVERY call. Seems wrong. FIX!!!!

Specified by:

prepare in interface RetryingCallable<Result[]>

Overrides:

prepare in class ScannerCallable

Parameters:

reload - force reload of server location

Throws:

IOException

locateRegionsInRange

private List<HRegionLocation> locateRegionsInRange(byte[] startKey,
                                                   byte[] endKey,
                                                   boolean reload)
                                            throws IOException

Get the corresponding regions for an arbitrary range of keys.

Parameters:

startKey - Starting row in range, inclusive

endKey - Ending row in range, exclusive

reload - force reload of server location

Returns:

A list of HRegionLocation corresponding to the regions that contain the specified range

Throws:

IOException

getScannerCallableForReplica

public ScannerCallable getScannerCallableForReplica(int id)

Overrides:

getScannerCallableForReplica in class ScannerCallable