org.apache.accumulo.core.client.mapred

Class AbstractInputFormat.AbstractRecordReader<K,V>

java.lang.Object

org.apache.accumulo.core.client.mapred.AbstractInputFormat.AbstractRecordReader<K,V>

All Implemented Interfaces:

org.apache.hadoop.mapred.RecordReader<K,V>

Direct Known Subclasses:

InputFormatBase.RecordReaderBase

Enclosing class:

AbstractInputFormat<K,V>

protected abstract static class AbstractInputFormat.AbstractRecordReader<K,V>
extends Object
implements org.apache.hadoop.mapred.RecordReader<K,V>

An abstract base class to be used to create RecordReader instances that convert from Accumulo Key/Value pairs to the user's K/V types. Subclasses must implement RecordReader.next(Object, Object) to update key and value, and also to update the following variables:

• Key currentKey (used for progress reporting)
• int numKeysRead (used for progress reporting)

Field Summary

Fields

Modifier and Type	Field and Description
protected Key	currentKey
protected long	numKeysRead
protected Iterator<Map.Entry<Key,Value>>	scannerIterator
protected RangeInputSplit	split

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractRecordReader()

Method Summary

Modifier and Type	Method and Description
void	close()
long	getPos()
float	getProgress()
void	initialize(org.apache.hadoop.mapred.InputSplit inSplit, org.apache.hadoop.mapred.JobConf job) Initialize a scanner over the given input split using this task attempt configuration.
protected abstract void	setupIterators(org.apache.hadoop.mapred.JobConf job, Scanner scanner, String tableName, RangeInputSplit split) Configures the iterators on a scanner for the given table name.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.mapred.RecordReader

createKey, createValue, next

Field Detail

numKeysRead

protected long numKeysRead

scannerIterator

protected Iterator<Map.Entry<Key,Value>> scannerIterator

split

protected RangeInputSplit split

currentKey

protected Key currentKey

Constructor Detail

AbstractRecordReader

protected AbstractRecordReader()

Method Detail

setupIterators

protected abstract void setupIterators(org.apache.hadoop.mapred.JobConf job,
                                       Scanner scanner,
                                       String tableName,
                                       RangeInputSplit split)

Configures the iterators on a scanner for the given table name.

Parameters:

job - the Hadoop job configuration

scanner - the scanner for which to configure the iterators

tableName - the table name for which the scanner is configured

Since:

1.6.0

initialize

public void initialize(org.apache.hadoop.mapred.InputSplit inSplit,
                       org.apache.hadoop.mapred.JobConf job)
                throws IOException

Initialize a scanner over the given input split using this task attempt configuration.

Throws:

IOException

close

public void close()

Specified by:

close in interface org.apache.hadoop.mapred.RecordReader<K,V>

getPos

public long getPos()
            throws IOException

Specified by:

getPos in interface org.apache.hadoop.mapred.RecordReader<K,V>

Throws:

IOException

getProgress

public float getProgress()
                  throws IOException

Specified by:

getProgress in interface org.apache.hadoop.mapred.RecordReader<K,V>

Throws:

IOException