package edu.northwestern.at.utils.corpuslinguistics.postagger.guesser;
/* Please see the license information at the end of this file. */
import java.util.*;
import edu.northwestern.at.utils.*;
import edu.northwestern.at.utils.corpuslinguistics.lexicon.*;
import edu.northwestern.at.utils.corpuslinguistics.postagger.*;
import edu.northwestern.at.utils.corpuslinguistics.spellingstandardizer.*;
/** Default part of speech guesser.
*
* <p>
* This default guesser returns a noun, number or punctuation tag.
* The lexicon provides the part of speech tags for these items.
* </p>
*/
public class DefaultPartOfSpeechGuesser
extends AbstractPartOfSpeechGuesser
implements PartOfSpeechGuesser
{
/** Guesses part of speech for a word.
*
* @param theWord The word.
*
* @return Guessed parts of speech.
*/
public Map<String, MutableInteger> guessPartsOfSpeech( String theWord )
{
if ( debug )
{
logger.logDebug( "guessPartsOfSpeech: word=" + theWord );
}
String word = theWord;
// Is word in cache? Return
// existing parts of speech if so.
Map<String, MutableInteger> result = checkCachedWord( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: in cache, pos=" + result
);
}
if ( result.size() == 0 ) result = null;
}
if ( result != null ) return result;
// If the word is in the word lexicon,
// get the parts of speech from
// the lexicon.
if ( wordLexicon != null )
{
if ( wordLexicon.containsEntry( word ) )
{
result =
clonePosTagMap
(
wordLexicon.getCategoryCountsForEntry( word )
);
}
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: in word lexicon, pos=" + result
);
}
}
if ( result != null ) return result;
// If the word is all caps,
// change it to first letter capitalized
// only for the remainder of the
// checks.
// word = EnglishDecruftifier.decruftify( word );
if ( CharUtils.allLettersCapital( word ) )
{
word = CharUtils.capitalizeFirstLetter( word );
// Look up recapitalized word
// in lexicon.
if ( wordLexicon.containsEntry( word ) )
{
result =
clonePosTagMap
(
wordLexicon.getCategoryCountsForEntry( word )
);
}
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: recapitalized in word " +
"lexicon, pos=" + result
);
}
}
if ( result != null ) return result;
}
}
// If punctuation, return that
// unchanged.
result = checkPunctuation( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is punctuation, pos=" + result
);
}
}
if ( result != null ) return result;
// If symbol, return that
// unchanged.
result = checkSymbol( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is symbol, pos=" + result
);
}
}
if ( result != null ) return result;
// See if it is a number.
result = checkNumber( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is number, pos=" + result
);
}
}
if ( result != null ) return result;
// See if it is currency.
result = checkCurrency( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is currency, pos=" + result
);
}
}
if ( result != null ) return result;
// See if it is an abbreviation.
result = checkAbbreviation( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is abbreviation, pos=" + result
);
}
}
if ( result != null ) return result;
// See if it is a Roman Numeral.
result = checkRomanNumeral( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is Roman numeral, pos=" +
result
);
}
}
if ( result != null ) return result;
// Check for hyphenated word.
result = checkHyphenatedWord( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is hyphenated word, pos=" +
result
);
}
}
if ( result != null ) return result;
// See if we have any standardized
// spellings for this word. If so,
// and the word is in the word lexicon,
// return the parts of speech for
// the standardized spellings.
String[] standardSpellings = getStandardizedSpellings( word );
if ( standardSpellings != null )
{
result = checkStandardSpellings( word , standardSpellings );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: from standard spellings, " +
"pos=" + result
);
}
}
if ( result != null ) return result;
}
// Standard spelling not found in
// lexicon.
// See if it is a proper name.
result = checkName( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is name, pos=" + result
);
}
}
if ( result != null ) return result;
// See if it is a possessive.
result = checkPossessiveNoun( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is possessive, pos=" + result
);
}
}
if ( result != null ) return result;
// See if word is in the auxiliary
// word lists.
result = checkAuxiliaryWordLists( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: from auxiliary word lists, " +
"pos=" + result
);
}
}
if ( result != null ) return result;
// Try looking at successively shorter
// suffixes and assign part of speech tags
// for the longest matching suffix in
// the suffix lexicon, if any.
if ( suffixLexicon != null )
{
result = checkSuffixes( word , standardSpellings );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: from suffix analysis, " +
"pos=" + result
);
}
}
if ( result != null ) return result;
}
// No suffix matched.
// If all uppercase, assume it is
// a noun.
result = checkAllUpperCase( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: is all uppercase, pos=" +
result
);
}
}
if ( result != null ) return result;
// Nothing matched so far.
// Assume word is a noun.
result = getNoun( word );
if ( result != null )
{
if ( debug )
{
logger.logDebug
(
"guessPartsOfSpeech: assigning noun, pos=" + result
);
}
}
return result;
}
/** Guesses part of speech for a word in a sentence.
*
* @param sentence Sentence as a list of words.
* @param wordIndex The word index in the sentence.
*
* @return Guessed parts of speech.
*/
public Map<String, MutableInteger> guessPartsOfSpeech
(
List<String> sentence ,
int wordIndex
)
{
String word = (String)sentence.get( wordIndex );
// Check for capitalized word not
// first word in sentence.
/*
if ( wordIndex > 0 )
{
// If word starts with a capital
// letter, assume it is a proper name.
if ( ( 'A' <= word.charAt( 0 ) ) && ( word.charAt( 0 ) <= 'Z' ) )
{
String[] result =
new String[]{ wordLexicon.getSingularProperNounPOS() };
addCachedWord( word , result );
return result;
}
}
*/
return guessPartsOfSpeech( word );
}
}
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