Package org.apache.hadoop.mapreduce.lib.input

Class SequenceFileInputFilter<K,V>

java.lang.Object

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

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

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

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

@Public
@Stable
public class SequenceFileInputFilter<K,V>
extends SequenceFileInputFormat<K,V>

A class that allows a map/red job to work on a sample of sequence files. The sample is decided by the filter class set by the job.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.Filter	filter interface
static class	org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.FilterBase	base class for Filters
static class	org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.MD5Filter	This class returns a set of records by examing the MD5 digest of its key against a filtering frequency f.
static class	org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.PercentFilter	This class returns a percentage of records The percentage is determined by a filtering frequency f using the criteria record# % f == 0.
static class	org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFilter.RegexFilter	Records filter by matching key to regex

Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.lib.input.FileInputFormat

FileInputFormat.Counter

Field Summary

Fields

Modifier and Type	Field	Description
static final String	FILTER_CLASS
static final String	FILTER_FREQUENCY
static final String	FILTER_REGEX
static final org.slf4j.Logger	LOG

Fields inherited from class org.apache.hadoop.mapreduce.lib.input.FileInputFormat

DEFAULT_LIST_STATUS_NUM_THREADS, INPUT_DIR, INPUT_DIR_NONRECURSIVE_IGNORE_SUBDIRS, INPUT_DIR_RECURSIVE, LIST_STATUS_NUM_THREADS, NUM_INPUT_FILES, PATHFILTER_CLASS, SPLIT_MAXSIZE, SPLIT_MINSIZE

Constructor Summary

Constructors

Constructor	Description
SequenceFileInputFilter()

Method Summary

Modifier and Type	Method	Description
RecordReader<K,V>	createRecordReader(InputSplit split, TaskAttemptContext context)	Create a record reader for the given split
static void	setFilterClass(Job job, Class<?> filterClass)	set the filter class

Methods inherited from class org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat

getFormatMinSplitSize, listStatus

Methods inherited from class org.apache.hadoop.mapreduce.lib.input.FileInputFormat

addInputPath, addInputPathRecursively, addInputPaths, computeSplitSize, getBlockIndex, getInputDirRecursive, getInputPathFilter, getInputPaths, getMaxSplitSize, getMinSplitSize, getSplits, isSplitable, makeSplit, makeSplit, setInputDirRecursive, setInputPathFilter, setInputPaths, setInputPaths, setMaxInputSplitSize, setMinInputSplitSize, shrinkStatus

Methods inherited from class java.lang.Object

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

Field Details

LOG

public static final org.slf4j.Logger LOG

FILTER_CLASS

public static final String FILTER_CLASS

See Also:

• Constant Field Values

FILTER_FREQUENCY

public static final String FILTER_FREQUENCY

See Also:

• Constant Field Values

FILTER_REGEX

public static final String FILTER_REGEX

See Also:

• Constant Field Values

Constructor Details

SequenceFileInputFilter

public SequenceFileInputFilter()

Method Details

createRecordReader

public RecordReader<K,V> createRecordReader(InputSplit split,
 TaskAttemptContext context)
                                     throws IOException

Create a record reader for the given split

Overrides:

createRecordReader in class SequenceFileInputFormat<K,V>

Parameters:

split - file split

context - the task-attempt context

Returns:

RecordReader

Throws:

IOException

setFilterClass

public static void setFilterClass(Job job,
 Class<?> filterClass)

set the filter class

Parameters:

job - The job

filterClass - filter class