org.apache.hadoop.hbase.client

类 ScannerCallable

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

所有已实现的接口:

RetryingCallable<Result[]>

直接已知子类:

ReversedScannerCallable

@InterfaceAudience.Private
public class ScannerCallable
extends ClientServiceCallable<Result[]>

Scanner operations such as create, next, etc. Used by ResultScanners made by Table. Passed to a retrying caller such as RpcRetryingCaller so fails are retried.

字段概要

字段

限定符和类型	字段和说明
protected boolean	closed
protected Cursor	cursor
protected boolean	heartbeatMessage Saves whether or not the most recent response from the server was a heartbeat message.
protected int	id
protected boolean	instantiated
protected boolean	isRegionServerRemote
static org.slf4j.Logger	LOG
static String	LOG_SCANNER_ACTIVITY
static String	LOG_SCANNER_LATENCY_CUTOFF
protected boolean	renew
protected RpcControllerFactory	rpcControllerFactory
protected Scan	scan
protected ScanMetrics	scanMetrics
protected long	scannerId

从类继承的字段 org.apache.hadoop.hbase.client.RegionServerCallable

location, rpcController, stub

构造器概要

构造器

构造器和说明
ScannerCallable(ClusterConnection connection, TableName tableName, Scan scan, ScanMetrics scanMetrics, RpcControllerFactory rpcControllerFactory)
ScannerCallable(ClusterConnection connection, TableName tableName, Scan scan, ScanMetrics scanMetrics, RpcControllerFactory rpcControllerFactory, int id)

方法概要

限定符和类型	方法和说明
protected void	checkIfRegionServerIsRemote() compare the local machine hostname with region server's hostname to decide if hbase client connects to a remote region server
int	getCaching() Get the number of rows that will be fetched on next
Cursor	getCursor()
HRegionInfo	getHRegionInfo()
protected Scan	getScan()
ScannerCallable	getScannerCallableForReplica(int id)
void	prepare(boolean reload) Prepare by setting up any connections to servers, etc., ahead of call invocation.
protected Result[]	rpcCall() Run the RPC call.
void	setCaching(int caching) Set the number of rows that will be fetched on next
void	setClose() Call this when the next invocation of call should close the scanner
void	setRenew(boolean val) Indicate whether we make a call only to renew the lease, but without affected the scanner in any other way.

从类继承的方法 org.apache.hadoop.hbase.client.ClientServiceCallable

doGet, doMutate, setStubByServiceName

从类继承的方法 org.apache.hadoop.hbase.client.RegionServerCallable

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

从类继承的方法 java.lang.Object

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

字段详细资料

LOG_SCANNER_LATENCY_CUTOFF

public static final String LOG_SCANNER_LATENCY_CUTOFF

另请参阅:

常量字段值

LOG_SCANNER_ACTIVITY

public static final String LOG_SCANNER_ACTIVITY

另请参阅:

常量字段值

LOG

public static final org.slf4j.Logger LOG

scannerId

protected long scannerId

instantiated

protected boolean instantiated

closed

protected boolean closed

renew

protected boolean renew

scan

protected final Scan scan

scanMetrics

protected ScanMetrics scanMetrics

id

protected final int id

heartbeatMessage

protected boolean heartbeatMessage

Saves whether or not the most recent response from the server was a heartbeat message. Heartbeat messages are identified by the flag ClientProtos.ScanResponse.getHeartbeatMessage()

cursor

protected Cursor cursor

isRegionServerRemote

protected boolean isRegionServerRemote

rpcControllerFactory

protected final RpcControllerFactory rpcControllerFactory

构造器详细资料

ScannerCallable

public ScannerCallable(ClusterConnection connection,
                       TableName tableName,
                       Scan scan,
                       ScanMetrics scanMetrics,
                       RpcControllerFactory rpcControllerFactory)

参数:

connection - which connection

tableName - table callable is on

scan - the scan to execute

scanMetrics - the ScanMetrics to used, if it is null, ScannerCallable won't collect metrics

rpcControllerFactory - factory to use when creating RpcController

ScannerCallable

public ScannerCallable(ClusterConnection connection,
                       TableName tableName,
                       Scan scan,
                       ScanMetrics scanMetrics,
                       RpcControllerFactory rpcControllerFactory,
                       int id)

参数:

connection -

tableName -

scan -

scanMetrics -

id - the replicaId

方法详细资料

prepare

public void prepare(boolean reload)
             throws IOException

从接口复制的说明: RetryingCallable

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

指定者:

prepare 在接口中 RetryingCallable<Result[]>

覆盖:

prepare 在类中 RegionServerCallable<Result[],org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.ClientService.BlockingInterface>

参数:

reload - force reload of server location

抛出:

IOException

checkIfRegionServerIsRemote

protected void checkIfRegionServerIsRemote()

compare the local machine hostname with region server's hostname to decide if hbase client connects to a remote region server

rpcCall

protected Result[] rpcCall()
                    throws Exception

从类复制的说明: RegionServerCallable

Run the RPC call. Implement this method. To get at the rpcController that has been created and configured to make this rpc call, use getRpcController(). We are trying to contain rpcController references so we don't pollute codebase with protobuf references; keep the protobuf references contained and only present in a few classes rather than all about the code base.

指定者:

rpcCall 在类中 RegionServerCallable<Result[],org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.ClientService.BlockingInterface>

抛出:

Exception

getCursor

public Cursor getCursor()

getScan

protected Scan getScan()

setClose

public void setClose()

Call this when the next invocation of call should close the scanner

setRenew

public void setRenew(boolean val)

Indicate whether we make a call only to renew the lease, but without affected the scanner in any other way.

参数:

val - true if only the lease should be renewed

getHRegionInfo

public HRegionInfo getHRegionInfo()

覆盖:

getHRegionInfo 在类中 RegionServerCallable<Result[],org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.ClientService.BlockingInterface>

返回:

the HRegionInfo for the current region

getCaching

public int getCaching()

Get the number of rows that will be fetched on next

返回:

the number of rows for caching

setCaching

public void setCaching(int caching)

Set the number of rows that will be fetched on next

参数:

caching - the number of rows for caching

getScannerCallableForReplica

public ScannerCallable getScannerCallableForReplica(int id)