org.apache.hadoop.mapreduce.lib.input

Class SequenceFileRecordReader<K,V>

java.lang.Object

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

org.apache.hadoop.mapreduce.lib.input.SequenceFileRecordReader<K,V>

All Implemented Interfaces:

Closeable, AutoCloseable

@InterfaceAudience.Public
 @InterfaceStability.Stable
public class SequenceFileRecordReader<K,V>
extends RecordReader<K,V>

An RecordReader for SequenceFiles.

Field Summary

Fields

Modifier and Type	Field and Description
protected Configuration	conf

Constructor Summary

Constructors

Constructor and Description
SequenceFileRecordReader()

Method Summary

Modifier and Type	Method and Description
void	close() Close the record reader.
K	getCurrentKey() Get the current key
V	getCurrentValue() Get the current value.
float	getProgress() Return the progress within the input split
void	initialize(InputSplit split, TaskAttemptContext context) Called once at initialization.
boolean	nextKeyValue() Read the next key, value pair.

Methods inherited from class java.lang.Object

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

Field Detail

conf

protected Configuration conf

Constructor Detail

SequenceFileRecordReader

public SequenceFileRecordReader()

Method Detail

initialize

public void initialize(InputSplit split,
                       TaskAttemptContext context)
                throws IOException,
                       InterruptedException

Description copied from class: RecordReader

Called once at initialization.

Specified by:

initialize in class RecordReader<K,V>

Parameters:

split - the split that defines the range of records to read

context - the information about the task

Throws:

IOException

InterruptedException

nextKeyValue

public boolean nextKeyValue()
                     throws IOException,
                            InterruptedException

Description copied from class: RecordReader

Read the next key, value pair.

Specified by:

nextKeyValue in class RecordReader<K,V>

Returns:

true if a key/value pair was read

Throws:

IOException

InterruptedException

getCurrentKey

public K getCurrentKey()

Description copied from class: RecordReader

Get the current key

Specified by:

getCurrentKey in class RecordReader<K,V>

Returns:

the current key or null if there is no current key

getCurrentValue

public V getCurrentValue()

Description copied from class: RecordReader

Get the current value.

Specified by:

getCurrentValue in class RecordReader<K,V>

Returns:

the object that was read

getProgress

public float getProgress()
                  throws IOException

Return the progress within the input split

Specified by:

getProgress in class RecordReader<K,V>

Returns:

0.0 to 1.0 of the input byte range

Throws:

IOException

close

public void close()
           throws IOException

Description copied from class: RecordReader

Close the record reader.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in class RecordReader<K,V>

Throws:

IOException