org.apache.hadoop.hbase.client

类 AbstractClientScanner

java.lang.Object

org.apache.hadoop.hbase.client.AbstractClientScanner

所有已实现的接口:

Closeable, AutoCloseable, Iterable<Result>, ResultScanner

直接已知子类:

ClientScanner

@InterfaceAudience.Private
public abstract class AbstractClientScanner
extends Object
implements ResultScanner

Helper class for custom client scanners.

字段概要

字段

限定符和类型	字段和说明
protected ScanMetrics	scanMetrics

构造器概要

构造器

构造器和说明
AbstractClientScanner()

方法概要

方法

限定符和类型	方法和说明
ScanMetrics	getScanMetrics() Used internally accumulating metrics on scan.
protected void	initScanMetrics(Scan scan) Check and initialize if application wants to collect scan metrics
Iterator<Result>	iterator()
Result[]	next(int nbRows) Get nbRows rows.
abstract boolean	renewLease() Allow the client to renew the scanner's lease on the server.

从类继承的方法 java.lang.Object

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

从接口继承的方法 org.apache.hadoop.hbase.client.ResultScanner

close, next

字段详细资料

scanMetrics

protected ScanMetrics scanMetrics

构造器详细资料

AbstractClientScanner

public AbstractClientScanner()

方法详细资料

initScanMetrics

protected void initScanMetrics(Scan scan)

Check and initialize if application wants to collect scan metrics

getScanMetrics

public ScanMetrics getScanMetrics()

Used internally accumulating metrics on scan. To enable collection of metrics on a Scanner, call Scan.setScanMetricsEnabled(boolean). These metrics are cleared at key transition points. Metrics are accumulated in the Scan object itself.

返回:

Returns the running ScanMetrics instance or null if scan metrics not enabled.

另请参阅:

Scan.getScanMetrics()

next

public Result[] next(int nbRows)
              throws IOException

Get nbRows rows. How many RPCs are made is determined by the Scan.setCaching(int) setting (or hbase.client.scanner.caching in hbase-site.xml).

指定者:

next 在接口中 ResultScanner

参数:

nbRows - number of rows to return

返回:

Between zero and nbRows RowResults. Scan is done if returned array is of zero-length (We never return null).

抛出:

IOException

iterator

public Iterator<Result> iterator()

指定者:

iterator 在接口中 Iterable<Result>

renewLease

public abstract boolean renewLease()

Allow the client to renew the scanner's lease on the server.

返回:

true if the lease was successfully renewed, false otherwise.