edu.umd.cloud9.collection.trec

Class TrecDocnoMapping

java.lang.Object

edu.umd.cloud9.collection.trec.TrecDocnoMapping

All Implemented Interfaces:

DocnoMapping

public class TrecDocnoMapping
extends Object
implements DocnoMapping

Object that maps between TREC docids (String identifiers) to docnos (sequentially-numbered ints). The main of this class provides a simple program for accessing docno mappings. Command-line arguments are as follows:

• list, getDocno, getDocid: the command—list all mappings; get docno from docid; or, get docid from docno
• [mappings-file]: the mappings file
• [docid/docno]: the docid or docno (optional)

Author:

Jimmy Lin

Nested Class Summary

Nested classes/interfaces inherited from interface edu.umd.cloud9.collection.DocnoMapping

DocnoMapping.Builder, DocnoMapping.BuilderUtils, DocnoMapping.DefaultBuilderOptions

Constructor Summary

Constructors

Constructor and Description
TrecDocnoMapping() Creates a TrecDocnoMapping object.

Method Summary

Methods

Modifier and Type	Method and Description
DocnoMapping.Builder	getBuilder() Returns the builder for this mapping.
String	getDocid(int docno) Returns the docid for a particular docno.
int	getDocno(String docid) Returns the docno for a particular docid.
void	loadMapping(org.apache.hadoop.fs.Path p, org.apache.hadoop.fs.FileSystem fs) Loads a mapping file.
static void	main(String[] args) Simple program the provides access to the docno/docid mappings.
static String[]	readMappingData(org.apache.hadoop.fs.Path p, org.apache.hadoop.fs.FileSystem fs) Reads a mappings file into memory.
static void	writeMappingData(org.apache.hadoop.fs.Path input, org.apache.hadoop.fs.Path output, org.apache.hadoop.fs.FileSystem fs) Creates a mappings file from the contents of a flat text file containing docid to docno mappings.

Methods inherited from class java.lang.Object

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

Constructor Detail

TrecDocnoMapping

public TrecDocnoMapping()

Creates a TrecDocnoMapping object.

Method Detail

getDocno

public int getDocno(String docid)

Description copied from interface: DocnoMapping

Returns the docno for a particular docid.

Specified by:

getDocno in interface DocnoMapping

Parameters:

docid - the docid

Returns:

the docno for the docid

getDocid

public String getDocid(int docno)

Description copied from interface: DocnoMapping

Returns the docid for a particular docno.

Specified by:

getDocid in interface DocnoMapping

Parameters:

docno - the docno

Returns:

the docid for the docno

loadMapping

public void loadMapping(org.apache.hadoop.fs.Path p,
               org.apache.hadoop.fs.FileSystem fs)
                 throws IOException

Description copied from interface: DocnoMapping

Loads a mapping file.

Specified by:

loadMapping in interface DocnoMapping

Parameters:

p - path to the mappings file

fs - reference to the FileSystem

Throws:

IOException

writeMappingData

public static void writeMappingData(org.apache.hadoop.fs.Path input,
                    org.apache.hadoop.fs.Path output,
                    org.apache.hadoop.fs.FileSystem fs)
                             throws IOException

Creates a mappings file from the contents of a flat text file containing docid to docno mappings. This method is used by TrecDocnoMappingBuilder internally.

Parameters:

input - flat text file containing docid to docno mappings

output - output mappings data file

fs - FileSystem to write to

Throws:

IOException

readMappingData

public static String[] readMappingData(org.apache.hadoop.fs.Path p,
                       org.apache.hadoop.fs.FileSystem fs)
                                throws IOException

Reads a mappings file into memory.

Parameters:

p - path to the mappings data file

fs - appropriate FileSystem

Returns:

an array of docids; the index position of each docid is its docno

Throws:

IOException

getBuilder

public DocnoMapping.Builder getBuilder()

Description copied from interface: DocnoMapping

Returns the builder for this mapping.

Specified by:

getBuilder in interface DocnoMapping

Returns:

builder for this mapping

main

public static void main(String[] args)
                 throws IOException

Simple program the provides access to the docno/docid mappings.

Throws:

IOException