org.terrier.structures.indexing.singlepass.hadoop

Class WritableByteArray

java.lang.Object

org.terrier.structures.indexing.singlepass.hadoop.WritableByteArray

All Implemented Interfaces:

org.apache.hadoop.io.Writable

Direct Known Subclasses:

MapEmittedPostingList

public class WritableByteArray
extends Object
implements org.apache.hadoop.io.Writable

Represents a Writable Posting List. This can contain in addition to the posting list, the Document Frequency and Term Frequency. This class is needed because Hadoop must know how to write out the intermediate map output during indexing

Since:

2.2

Author:

Richard McCreadie

Field Summary

Fields

Modifier and Type	Field and Description
protected byte[]	array Posting List
protected int	arraylength Size of the Posting List
protected int	DocumentFreq Document Frequency
protected int	TermFreq Term Frequency

Constructor Summary

Constructors

Constructor and Description
WritableByteArray() Empty Constructor
WritableByteArray(int c) Constructor - with Document Frequency
WritableByteArray(int c, int c2) Constructor - with Document Frequency and Term Frequency

Method Summary

Methods

Modifier and Type	Method and Description
static WritableByteArray	create_Hadoop_WritableByteArray(byte[] b) Factory Method
static WritableByteArray	create_Hadoop_WritableByteArray(byte[] b, int c) Factory Method
static WritableByteArray	create_Hadoop_WritableByteArray(byte[] b, int c, int c2) Factory Method
byte[]	getArray() Gets the byte array
int	getDocumentFreq() Get the document frequency
int	getTermFreq() Get the term frequency
void	readFields(DataInput arg0) Read this object from the input stream 'in'
void	setArray(byte[] b) Sets the byte array
void	setDocumentFreq(int _DocumentFreq) Set the document frequency
void	setTermFrequency(int _TermFreq) Set the term frequency
String	toString()
void	write(DataOutput arg0) Write this object to the output stream 'out'

Methods inherited from class java.lang.Object

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

Field Detail

array

protected byte[] array

Posting List

DocumentFreq

protected int DocumentFreq

Document Frequency

TermFreq

protected int TermFreq

Term Frequency

arraylength

protected int arraylength

Size of the Posting List

Constructor Detail

WritableByteArray

public WritableByteArray()

Empty Constructor

WritableByteArray

public WritableByteArray(int c)

Constructor - with Document Frequency

Parameters:

c - - Document Frequency

WritableByteArray

public WritableByteArray(int c,
                 int c2)

Constructor - with Document Frequency and Term Frequency

Parameters:

c - - Document Frequency

c2 - - Term Frequency

Method Detail

create_Hadoop_WritableByteArray

public static WritableByteArray create_Hadoop_WritableByteArray(byte[] b)
                                                         throws IOException

Factory Method

Parameters:

b - - Posting List

Returns:

a newly created object

Throws:

IOException

create_Hadoop_WritableByteArray

public static WritableByteArray create_Hadoop_WritableByteArray(byte[] b,
                                                int c)
                                                         throws IOException

Factory Method

Parameters:

b - - Posting List

c - - Document Frequency

Returns:

a newly created object

Throws:

IOException

create_Hadoop_WritableByteArray

public static WritableByteArray create_Hadoop_WritableByteArray(byte[] b,
                                                int c,
                                                int c2)
                                                         throws IOException

Factory Method

Parameters:

b - - Posting List

c - - Document Frequency

c2 - - Term Frequency

Returns:

a newly created Indexing_WritableByteArray

Throws:

IOException

readFields

public void readFields(DataInput arg0)
                throws IOException

Read this object from the input stream 'in'

Specified by:

readFields in interface org.apache.hadoop.io.Writable

Throws:

IOException

write

public void write(DataOutput arg0)
           throws IOException

Write this object to the output stream 'out'

Specified by:

write in interface org.apache.hadoop.io.Writable

Throws:

IOException

setArray

public void setArray(byte[] b)

Sets the byte array

getArray

public byte[] getArray()

Gets the byte array

toString

public String toString()

Overrides:

toString in class Object

getDocumentFreq

public int getDocumentFreq()

Get the document frequency

setDocumentFreq

public void setDocumentFreq(int _DocumentFreq)

Set the document frequency

getTermFreq

public int getTermFreq()

Get the term frequency

setTermFrequency

public void setTermFrequency(int _TermFreq)

Set the term frequency