org.apache.flink.addons.hbase

Class TableInputFormat<T extends Tuple>

java.lang.Object

org.apache.flink.api.common.io.RichInputFormat<T,TableInputSplit>

org.apache.flink.addons.hbase.AbstractTableInputFormat<T>

org.apache.flink.addons.hbase.TableInputFormat<T>

All Implemented Interfaces:

Serializable, InputFormat<T,TableInputSplit>, InputSplitSource<TableInputSplit>

public abstract class TableInputFormat<T extends Tuple>
extends AbstractTableInputFormat<T>

InputFormat subclass that wraps the access for HTables.

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.flink.addons.hbase.AbstractTableInputFormat

currentRow, endReached, LOG, resultScanner, scan, scannedRows, table

Constructor Summary

Constructors

Constructor and Description
TableInputFormat()

Method Summary

Modifier and Type	Method and Description
void	configure(Configuration parameters) Creates a Scan object and opens the HTable connection.
protected abstract org.apache.hadoop.hbase.client.Scan	getScanner() Returns an instance of Scan that retrieves the required subset of records from the HBase table.
protected abstract String	getTableName() What table is to be read.
protected T	mapResultToOutType(org.apache.hadoop.hbase.client.Result r) HBase returns an instance of Result.
protected abstract T	mapResultToTuple(org.apache.hadoop.hbase.client.Result r) The output from HBase is always an instance of Result.

Methods inherited from class org.apache.flink.addons.hbase.AbstractTableInputFormat

close, closeInputFormat, createInputSplits, getInputSplitAssigner, getStatistics, includeRegionInScan, nextRecord, open, reachedEnd

Methods inherited from class org.apache.flink.api.common.io.RichInputFormat

getRuntimeContext, openInputFormat, setRuntimeContext

Methods inherited from class java.lang.Object

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

Constructor Detail

TableInputFormat

public TableInputFormat()

Method Detail

getScanner

protected abstract org.apache.hadoop.hbase.client.Scan getScanner()

Returns an instance of Scan that retrieves the required subset of records from the HBase table.

Specified by:

getScanner in class AbstractTableInputFormat<T extends Tuple>

Returns:

The appropriate instance of Scan for this usecase.

getTableName

protected abstract String getTableName()

What table is to be read. Per instance of a TableInputFormat derivative only a single tablename is possible.

Specified by:

getTableName in class AbstractTableInputFormat<T extends Tuple>

Returns:

The name of the table

mapResultToTuple

protected abstract T mapResultToTuple(org.apache.hadoop.hbase.client.Result r)

The output from HBase is always an instance of Result. This method is to copy the data in the Result instance into the required Tuple

Parameters:

r - The Result instance from HBase that needs to be converted

Returns:

The appropriate instance of Tuple that contains the needed information.

configure

public void configure(Configuration parameters)

Creates a Scan object and opens the HTable connection. These are opened here because they are needed in the createInputSplits which is called before the openInputFormat method. So the connection is opened in configure(Configuration) and closed in AbstractTableInputFormat.closeInputFormat().

Specified by:

configure in interface InputFormat<T extends Tuple,TableInputSplit>

Specified by:

configure in class AbstractTableInputFormat<T extends Tuple>

Parameters:

parameters - The configuration that is to be used

See Also:

Configuration

mapResultToOutType

protected T mapResultToOutType(org.apache.hadoop.hbase.client.Result r)

Description copied from class: AbstractTableInputFormat

HBase returns an instance of Result.

This method maps the returned Result instance into the output type T.

Specified by:

mapResultToOutType in class AbstractTableInputFormat<T extends Tuple>

Parameters:

r - The Result instance from HBase that needs to be converted

Returns:

The appropriate instance of T that contains the data of Result.