org.apache.hadoop.hbase.client

类 ClientSmallReversedScanner

java.lang.Object

org.apache.hadoop.hbase.client.AbstractClientScanner

org.apache.hadoop.hbase.client.ClientScanner

org.apache.hadoop.hbase.client.ReversedClientScanner

org.apache.hadoop.hbase.client.ClientSmallReversedScanner

所有已实现的接口:

Closeable, AutoCloseable, Iterable<Result>, ResultScanner

@InterfaceAudience.Private
public class ClientSmallReversedScanner
extends ReversedClientScanner

Client scanner for small reversed scan. Generally, only one RPC is called to fetch the scan results, unless the results cross multiple regions or the row count of results exceed the caching.

For small scan, it will get better performance than ReversedClientScanner

字段概要

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

cache, caching, callable, caller, closed, conf, currentRegion, lastNext, lastResult, maxScannerResultSize, pool, primaryOperationTimeout, rpcControllerFactory, scan, scanMetricsPublished, scannerTimeout

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

scanMetrics

构造器概要

构造器

构造器和说明
ClientSmallReversedScanner(org.apache.hadoop.conf.Configuration conf, Scan scan, org.apache.hadoop.hbase.TableName tableName, ClusterConnection connection, RpcRetryingCallerFactory rpcFactory, RpcControllerFactory controllerFactory, ExecutorService pool, int primaryOperationTimeout) Create a new ReversibleClientScanner for the specified table.

方法概要

方法

限定符和类型	方法和说明
void	close() Closes the scanner and releases any resources it has allocated
protected void	initializeScannerInConstruction()
protected void	loadCache() Contact the servers to load more Results in the cache.
Result	next() Grab the next row's worth of values.
protected void	setScannerCallableFactory(ClientSmallScanner.SmallScannerCallableFactory callableFactory)

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

checkScanStopRow, createClosestRowBefore, getScannerCallable, nextScanner

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

getCacheSize, getCaching, getConf, getConnection, getMaxResultSize, getPool, getPrimaryOperationTimeout, getRetries, getScan, getScannerCallable, getScannerTimeout, getTable, getTableName, getTimestamp, renewLease, writeScanMetrics

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

getScanMetrics, initScanMetrics, iterator, next

从类继承的方法 java.lang.Object

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

构造器详细资料

ClientSmallReversedScanner

public ClientSmallReversedScanner(org.apache.hadoop.conf.Configuration conf,
                          Scan scan,
                          org.apache.hadoop.hbase.TableName tableName,
                          ClusterConnection connection,
                          RpcRetryingCallerFactory rpcFactory,
                          RpcControllerFactory controllerFactory,
                          ExecutorService pool,
                          int primaryOperationTimeout)
                           throws IOException

Create a new ReversibleClientScanner for the specified table. Take note that the passed Scan 's start row maybe changed changed.

参数:

conf - The Configuration to use.

scan - Scan to use in this scanner

tableName - The table that we wish to rangeGet

connection - Connection identifying the cluster

rpcFactory - Factory used to create the RpcRetryingCaller

controllerFactory - Factory used to access RPC payloads

pool - Threadpool for RPC threads

primaryOperationTimeout - Call timeout

抛出:

IOException - If the remote call fails

方法详细资料

next

public Result next()
            throws IOException

从接口复制的说明: ResultScanner

Grab the next row's worth of values. The scanner will return a Result.

指定者:

next 在接口中 ResultScanner

覆盖:

next 在类中 ClientScanner

返回:

Result object if there is another row, null if the scanner is exhausted.

抛出:

IOException - e

loadCache

protected void loadCache()
                  throws IOException

从类复制的说明: ClientScanner

Contact the servers to load more Results in the cache.

覆盖:

loadCache 在类中 ClientScanner

抛出:

IOException

initializeScannerInConstruction

protected void initializeScannerInConstruction()
                                        throws IOException

覆盖:

initializeScannerInConstruction 在类中 ClientScanner

抛出:

IOException

close

public void close()

从接口复制的说明: ResultScanner

Closes the scanner and releases any resources it has allocated

指定者:

close 在接口中 Closeable

指定者:

close 在接口中 AutoCloseable

指定者:

close 在接口中 ResultScanner

覆盖:

close 在类中 ClientScanner

setScannerCallableFactory

protected void setScannerCallableFactory(ClientSmallScanner.SmallScannerCallableFactory callableFactory)