gate.creole.annic.lucene
Class LuceneIndexer

java.lang.Object
  gate.creole.annic.lucene.LuceneIndexer

All Implemented Interfaces:

Indexer

public class LuceneIndexer
extends Object
implements Indexer

This class provides a Lucene based implementation for the Indexer interface. It asks users to provide various required parameters and creates the Lucene Index.

Author:

niraj

Field Summary

protected Corpus	corpus An corpus for indexing
protected boolean	DEBUG
protected Map	parameters Various parameters such as location of the Index etc.

Constructor Summary

LuceneIndexer(URL indexLocationUrl)
Constructor

Method Summary

void	add(String corpusPersistenceID, List<Document> added) Add new documents to Index
protected void	checkIndexParameters(Map parameters) Checks the Index Parameters to see if they are all compatible
void	createIndex(Map indexParameters) Creates index directory and indexing all documents in the corpus.
void	deleteIndex() Deletes the index.
private String	getCompatibleName(String name)
Corpus	getCorpus() Returns the corpus.
protected Map	getIndexParameters() Returns the indexing parameters
private List<Document>	getLuceneDocuments(String corpusPersistenceID, Document gateDoc, String location) We create a separate Lucene document for each index unit available in the gate document.
Set<String>	getNamesOfSerializedFiles(String documentID) This method returns a set of annotation set names that are indexed.
Map	getParameters() Returns the set parameters
void	optimizeIndex() Optimize existing index.
private void	readParametersFromDisk(URL indexLocationUrl) This method, searchers for the LuceneIndexDefinition.xml file at the provided location.
void	remove(List removedIDs) remove documents from the Index
void	setCorpus(Corpus corpus) Sets the corpus.
private void	writeParametersToDisk() All Index parameters are stored on a disc at the index_location_url/LuceneIndexDefinition.xml file.

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

protected boolean DEBUG

corpus

protected Corpus corpus

An corpus for indexing

parameters

protected Map parameters

Various parameters such as location of the Index etc.

Constructor Detail

LuceneIndexer

public LuceneIndexer(URL indexLocationUrl)
              throws IOException

Constructor

Parameters:

indexLocationUrl -

Throws:

IOException

Method Detail

checkIndexParameters

protected void checkIndexParameters(Map parameters)
                             throws IndexException

Checks the Index Parameters to see if they are all compatible

Throws:

IndexException

getIndexParameters

protected Map getIndexParameters()

Returns the indexing parameters

Returns:

createIndex

public void createIndex(Map indexParameters)
                 throws IndexException

Creates index directory and indexing all documents in the corpus.

Specified by:

createIndex in interface Indexer

Parameters:

indexParameters - This is a map containing various values required to create an index In case of LuceneIndexManager following are the values required

INDEX_LOCATION_URL - this is a URL where the Index be created

BASE_TOKEN_ANNOTATION_TYPE

INDEX_UNIT_ANNOTATION_TYPE

FEATURES_TO_EXCLUDE

FEATURES_TO_INCLUDE

Throws:

IndexException

optimizeIndex

public void optimizeIndex()
                   throws IndexException

Optimize existing index.

Specified by:

optimizeIndex in interface Indexer

Throws:

IndexException

deleteIndex

public void deleteIndex()
                 throws IndexException

Deletes the index.

Specified by:

deleteIndex in interface Indexer

Throws:

IndexException

add

public void add(String corpusPersistenceID,
                List<Document> added)
         throws IndexException

Add new documents to Index

Specified by:

add in interface Indexer

Parameters:

corpusPersistenceID -

addedDocuments -

Throws:

IndexException

getCompatibleName

private String getCompatibleName(String name)

remove

public void remove(List removedIDs)
            throws IndexException

remove documents from the Index

Specified by:

remove in interface Indexer

Parameters:

removedDocumentPersistenceIds - - when documents are not peristed, Persistence IDs will not be available In that case provide the document Names instead of their IDs

Throws:

Exception

IndexException

getLuceneDocuments

private List<Document> getLuceneDocuments(String corpusPersistenceID,
                                          Document gateDoc,
                                          String location)
                                   throws IndexException

We create a separate Lucene document for each index unit available in the gate document. An array of Lucene document is returned as a call to this method. It uses various indexing parameters set earlier.

Parameters:

corpusPersistenceID -

gateDoc -

location -

Returns:

Throws:

IndexException

getCorpus

public Corpus getCorpus()

Returns the corpus.

Specified by:

getCorpus in interface Indexer

Returns:

setCorpus

public void setCorpus(Corpus corpus)
               throws IndexException

Sets the corpus.

Specified by:

setCorpus in interface Indexer

Throws:

IndexException

readParametersFromDisk

private void readParametersFromDisk(URL indexLocationUrl)
                             throws IOException

This method, searchers for the LuceneIndexDefinition.xml file at the provided location. The file is supposed to contain all the required parameters which are used to create an index.

Parameters:

indexLocationUrl -

Throws:

IOException

writeParametersToDisk

private void writeParametersToDisk()
                            throws IOException

All Index parameters are stored on a disc at the index_location_url/LuceneIndexDefinition.xml file.

Throws:

IOException

getParameters

public Map getParameters()

Returns the set parameters

Specified by:

getParameters in interface Indexer

Returns:

getNamesOfSerializedFiles

public Set<String> getNamesOfSerializedFiles(String documentID)
                                      throws IndexException

This method returns a set of annotation set names that are indexed.

Returns:

Throws:

IndexException