Package org.apache.lucene.analysis.hunspell

Class Suggester

java.lang.Object

org.apache.lucene.analysis.hunspell.Suggester

public class Suggester
extends Object

A generator for misspelled word corrections based on Hunspell flags. The suggestions are searched for in two main ways:

1. Modification: trying to insert/remove/delete/swap parts of the word to get something acceptable. The performance of this part depends heavily on the contents of TRY, MAP, REP, KEY directives in the .aff file. To speed up this part, consider using withFragmentChecker(org.apache.lucene.analysis.hunspell.FragmentChecker).
2. Enumeration: if the modification hasn't produced "good enough" suggestions, the whole dictionary is scanned and simple affixes are added onto the entries to check if that produces anything similar to the given misspelled word. This depends on the dictionary size and the affix count, and it can take noticeable amount of time. To speed this up, withSuggestibleEntryCache() can be used.

Constructor Summary

Constructors

Constructor	Description
Suggester(Dictionary dictionary)

Method Summary

Modifier and Type	Method	Description
List<String>	suggestNoTimeout(String word, Runnable checkCanceled)	Compute suggestions for the given misspelled word
List<String>	suggestWithTimeout(String word, long timeLimitMs, Runnable checkCanceled)
Suggester	withFragmentChecker(FragmentChecker checker)	Returns a copy of this suggester instance with FragmentChecker hint that can improve the performance of the "Modification" phase performance.
Suggester	withSuggestibleEntryCache()	Returns a copy of this suggester instance with better "Enumeration" phase performance (see Suggester documentation), but using more memory.

Methods inherited from class java.lang.Object

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

Constructor Detail

Suggester

public Suggester(Dictionary dictionary)

Method Detail

withSuggestibleEntryCache

public Suggester withSuggestibleEntryCache()

Returns a copy of this suggester instance with better "Enumeration" phase performance (see Suggester documentation), but using more memory. With this option, the dictionary entries are stored as fast-to-iterate plain words instead of highly compressed prefix trees.

withFragmentChecker

public Suggester withFragmentChecker(FragmentChecker checker)

Returns a copy of this suggester instance with FragmentChecker hint that can improve the performance of the "Modification" phase performance.

suggestNoTimeout

public List<String> suggestNoTimeout(String word,
                                     Runnable checkCanceled)

Compute suggestions for the given misspelled word

Parameters:

word - the misspelled word to calculate suggestions for

checkCanceled - an object that's periodically called, allowing to interrupt or suggestion generation by throwing an exception

suggestWithTimeout

public List<String> suggestWithTimeout(String word,
                                       long timeLimitMs,
                                       Runnable checkCanceled)
                                throws SuggestionTimeoutException

Parameters:

word - the misspelled word to calculate suggestions for

timeLimitMs - the duration limit in milliseconds after which the computation is interruped by an exception

checkCanceled - an object that's periodically called, allowing to interrupt or suggestion generation by throwing an exception

Throws:

SuggestionTimeoutException - if the computation takes too long. Use SuggestionTimeoutException.getPartialResult() to get the suggestions computed up to that point