com.jalios.jcms.search.spell
Class SpellChecker

java.lang.Object
  com.jalios.jcms.search.spell.SpellChecker

public class SpellChecker
extends Object

Spell Checker class (Main class)
(initially inspired by the David Spencer code).

Example Usage:

  SpellChecker spellchecker = new SpellChecker(spellIndexDirectory);
  // To index a field of a user index:
  spellchecker.indexDictionary(new LuceneDictionary(my_lucene_reader, a_field));
  // To index a file containing words:
  spellchecker.indexDictionary(new PlainTextDictionary(new File("myfile.txt")));
  String[] suggestions = spellchecker.suggestSimilar("misspelt", 5);
 

Version:

1.0 - $Revision: 17654 $

Author:

Nicolas Maisonneuve, Olivier Jaquemet

Nested Class Summary

class

SpellChecker.IndexSearcherWrapper For optimized used of the searcher, we keep it open as much as possible and delay its close only when it is replaced by a new one when modifying index.

Field Summary

static String	MAX_BUFFERED_DOCS Optionnal integer property name to define the maxBufferedDocs when writing in spellchecker index
static String	MAX_MERGE_DOCS Optionnal integer property name to define the maxMergeDocs when writing in spellchecker index
static String	MERGE_FACTOR Optionnal integer property name to define the mergeFactor when writing in spellchecker index
static String	REVISION

Constructor Summary

SpellChecker(org.apache.lucene.store.Directory gramIndex)
Build a new SpellChecker.

Method Summary

void	clearIndex() Completely clear index from its content
void	closeAll()
boolean	exist(String word) Check whether the word exists in the index.
void	indexDictionary(Dictionary dict) Index a Dictionary
void	renewReaderAndSeacher() Renew internal reader and searcher, call this method after index change.
String[]	suggestSimilar(String word, int num_sug) Suggest similar words
String[]	suggestSimilar(String word, int num_sug, org.apache.lucene.index.IndexReader ir, String field, boolean morePopular) Suggest similar words (restricted or not to a field of a user index)

Methods inherited from class java.lang.Object

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

Field Detail

REVISION

public static final String REVISION

See Also:

Constant Field Values

MERGE_FACTOR

public static final String MERGE_FACTOR

Optionnal integer property name to define the mergeFactor when writing in spellchecker index

MAX_MERGE_DOCS

public static final String MAX_MERGE_DOCS

Optionnal integer property name to define the maxMergeDocs when writing in spellchecker index

MAX_BUFFERED_DOCS

public static final String MAX_BUFFERED_DOCS

Optionnal integer property name to define the maxBufferedDocs when writing in spellchecker index

Constructor Detail

SpellChecker

public SpellChecker(org.apache.lucene.store.Directory gramIndex)
             throws IOException

Build a new SpellChecker.

Parameters:

gramIndex - the lucene directory in which to look and put indexed words (grams)

Throws:

IOException

Method Detail

closeAll

public void closeAll()

suggestSimilar

public String[] suggestSimilar(String word,
                               int num_sug)
                        throws IOException

Suggest similar words

Parameters:

word - String the word you want a spell check done on

num_sug - int the number of suggest words

Returns:

String[]

Throws:

IOException

suggestSimilar

public String[] suggestSimilar(String word,
                               int num_sug,
                               org.apache.lucene.index.IndexReader ir,
                               String field,
                               boolean morePopular)
                        throws IOException

Suggest similar words (restricted or not to a field of a user index)

Parameters:

word - String the word you want a spell check done on

num_sug - int the number of suggest words

ir - the indexReader of the user index (can be null see field param)

field - String the field of the user index: if field is not null, the suggested words are restricted to the words present in this field.

morePopular - boolean return only the suggest words that are more frequent than the searched word (only if restricted mode = (indexReader!=null and field!=null)

Returns:

String[] the sorted list of the suggest words with this 2 criteria: first criteria: the edit distance, second criteria (only if restricted mode): the popularity of the suggest words in the field of the user index

Throws:

IOException

exist

public boolean exist(String word)
              throws IOException

Check whether the word exists in the index.

Parameters:

word - String

Returns:

true if the word exists in the index

Throws:

IOException

indexDictionary

public void indexDictionary(Dictionary dict)
                     throws IOException

Index a Dictionary

Parameters:

dict - the dictionary to index

Throws:

IOException

clearIndex

public void clearIndex()
                throws IOException

Completely clear index from its content

Throws:

IOException

renewReaderAndSeacher

public void renewReaderAndSeacher()
                           throws IOException

Renew internal reader and searcher, call this method after index change.

Throws:

IOException