org.apache.hawq.pxf.plugins.hive

Class HiveAccessor

java.lang.Object

org.apache.hawq.pxf.api.utilities.Plugin

org.apache.hawq.pxf.plugins.hdfs.HdfsSplittableDataAccessor

org.apache.hawq.pxf.plugins.hive.HiveAccessor

All Implemented Interfaces:

ReadAccessor

Direct Known Subclasses:

HiveLineBreakAccessor, HiveRCFileAccessor

public class HiveAccessor
extends HdfsSplittableDataAccessor

Accessor for Hive tables. The accessor will open and read a split belonging to a Hive table. Opening a split means creating the corresponding InputFormat and RecordReader required to access the split's data. The actual record reading is done in the base class - HdfsSplittableDataAccessor.
HiveAccessor will also enforce Hive partition filtering by filtering-out a split which does not belong to a partition filter. Naturally, the partition filtering will be done only for Hive tables that are partitioned.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.Boolean	filterInFragmenter

Fields inherited from class org.apache.hawq.pxf.plugins.hdfs.HdfsSplittableDataAccessor

conf, data, inputFormat, iter, jobConf, key, reader

Fields inherited from class org.apache.hawq.pxf.api.utilities.Plugin

inputData

Constructor Summary

Constructors

Constructor and Description
HiveAccessor(InputData input) Constructs a HiveAccessor and creates an InputFormat (derived from InputFormat) and the Hive partition fields
HiveAccessor(InputData input, org.apache.hadoop.mapred.InputFormat<?,?> inputFormat) Constructs a HiveAccessor

Method Summary

Modifier and Type	Method and Description
protected java.lang.Object	getReader(org.apache.hadoop.mapred.JobConf jobConf, org.apache.hadoop.mapred.InputSplit split) Creates the RecordReader suitable for this given split.
boolean	openForRead() Opens Hive data split for read.

Methods inherited from class org.apache.hawq.pxf.plugins.hdfs.HdfsSplittableDataAccessor

closeForRead, getNextSplit, isThreadSafe, readNextObject

Methods inherited from class java.lang.Object

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

Field Detail

filterInFragmenter

protected java.lang.Boolean filterInFragmenter

Constructor Detail

HiveAccessor

public HiveAccessor(InputData input)
             throws java.lang.Exception

Constructs a HiveAccessor and creates an InputFormat (derived from InputFormat) and the Hive partition fields

Parameters:

input - contains the InputFormat class name and the partition fields

Throws:

java.lang.Exception - if failed to create input format

HiveAccessor

public HiveAccessor(InputData input,
                    org.apache.hadoop.mapred.InputFormat<?,?> inputFormat)

Constructs a HiveAccessor

Parameters:

input - contains the InputFormat class name and the partition fields

inputFormat - Hive InputFormat

Method Detail

openForRead

public boolean openForRead()
                    throws java.lang.Exception

Opens Hive data split for read. Enables Hive partition filtering.

Specified by:

openForRead in interface ReadAccessor

Overrides:

openForRead in class HdfsSplittableDataAccessor

Returns:

true if there are no partitions or there is no partition filter or partition filter is set and the file currently opened by the accessor belongs to the partition.

Throws:

java.lang.Exception - if filter could not be built, connection to Hive failed or resource failed to open

getReader

protected java.lang.Object getReader(org.apache.hadoop.mapred.JobConf jobConf,
                                     org.apache.hadoop.mapred.InputSplit split)
                              throws java.io.IOException

Creates the RecordReader suitable for this given split.

Specified by:

getReader in class HdfsSplittableDataAccessor

Parameters:

jobConf - configuration data for the Hadoop framework

split - the split that was allocated for reading to this accessor

Returns:

record reader

Throws:

java.io.IOException - if failed to create record reader