danbikel.wordnet
Class Morphy

java.lang.Object
  |
  +--danbikel.wordnet.Morphy

All Implemented Interfaces:

MorphyRemote, Remote, Serializable

public class Morphy

extends Object

implements Serializable, MorphyRemote

Implementation of morphological analyzer Morphy that is part of WordNet.

See Also:

Serialized Form

Field Summary

protected static String[][]	adjSuffixes Array of two-element String arrays, where the first element of each two-element array is a potential adjective suffix and the second element is a replacement suffix to canonicalize the word form.
protected boolean[]	allCached
protected HashMap[]	cache
protected WNFile[]	excFiles Array of WNFile objects, representing exception lists for each of the three morphable parts of speech: nouns, verbs and adjectives.
protected static String	extension Filename extension for WordNet exception list files.
protected static String	fileSep Cache of the file separator obtained by calling System.getProperty(java.lang.String) with "file.separator".
protected static String[][]	nounSuffixes Array of two-element String arrays, where the first element of each two-element array is a potential noun suffix and the second element is a replacement suffix to canonicalize the word form.
protected static String[]	prepArr Array of prepositions.
protected static HashSet	prepositions Hashed set of String objects in prepArr, used for determining if a collocation contains a preposition.
protected static String[][][]	suffixArr Array containing references to suffix arrays nounSuffixes, verbSuffixes and adjSuffixes.
protected static String[][]	verbSuffixes Array of two-element String arrays, where the first element of each two-element array is a potential verb suffix and the second element is a replacement suffix to canonicalize the word form.
protected WordNet	wn Reference to WordNet object.

Constructor Summary

Morphy(WordNet wn)
Initialize a new Morphy object for finding lemmas for instances of words or collocations.

Method Summary

void	cacheAll()
void	cacheAll(int posIdx)
void	cacheAll(String pos)
protected static boolean	containsNonAlnum(String s) Predicate for determining if any characters in s are non-alphanumeric.
static int	countWords(String s, char separator) Same as countWords, but with word-delimiters specifically set to separator, ' ' and '_'.
static int	countWords(String s, String delim) Counts number of tokens in s separated by the delimiter characters specified by delim.
protected String[]	exceptionLookup(String str, String pos) Looks up exceptions for str in the WordNet exception file for pos
protected static String[][]	getSuffix(int posIdx) Gets the suffix array for a particular part of speech, either nounSuffixes, verbSuffixes or adjSuffixes.
protected static String[][]	getSuffix(String pos) Gets the suffix array for a particular part of speech, either nounSuffixes, verbSuffixes or adjSuffixes.
protected boolean	hasPrep(String str) Returns true if any word in (assumed collocated) str other than first or last contains a preposition.
static void	main(String[] args) Simple test driver for Morphy, reading one word/collocation per line from System.in, and spitting out possible morphs for each of the three morphable parts of speech: nouns, verbs and ajdectives.
protected String[]	morphPrep(String str) Tries to find morphs for str, which is assumed to be a collocation containing a verb, a preposition and a noun.
String[]	morphStr(String origstr, String pos) Tries several techniques on origstr to find possible base forms (lemmas).
protected String	morphWord(String word, String pos) Tries to find morph of a single word
protected String	wordBase(String word, String[][] suffixes, int sufIdx) Tries to form the base form of a word using information in a suffix lookup table.

Methods inherited from class java.lang.Object

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

Field Detail

fileSep

protected static String fileSep

Cache of the file separator obtained by calling System.getProperty(java.lang.String) with "file.separator".

nounSuffixes

protected static String[][] nounSuffixes

Array of two-element String arrays, where the first element of each two-element array is a potential noun suffix and the second element is a replacement suffix to canonicalize the word form. These arrays are accessed by getSuffix.

verbSuffixes

protected static String[][] verbSuffixes

Array of two-element String arrays, where the first element of each two-element array is a potential verb suffix and the second element is a replacement suffix to canonicalize the word form. These arrays are accessed by getSuffix.

adjSuffixes

protected static String[][] adjSuffixes

Array of two-element String arrays, where the first element of each two-element array is a potential adjective suffix and the second element is a replacement suffix to canonicalize the word form. These arrays are accessed by getSuffix.

suffixArr

protected static String[][][] suffixArr

Array containing references to suffix arrays nounSuffixes, verbSuffixes and adjSuffixes. Each of these suffix arrays is an array of two-element String arrays, where the first element is a potential suffix and the second element is a possible replacement suffix when attempting to find a base form of a word.

See Also:

getSuffix(int), getSuffix(String), wordBase(String, String[][], int)

prepArr

protected static final String[] prepArr

Array of prepositions.

prepositions

protected static final HashSet prepositions

Hashed set of String objects in prepArr, used for determining if a collocation contains a preposition.

extension

protected static String extension

Filename extension for WordNet exception list files.

wn

protected WordNet wn

Reference to WordNet object.

excFiles

protected WNFile[] excFiles

Array of WNFile objects, representing exception lists for each of the three morphable parts of speech: nouns, verbs and adjectives.

cache

protected HashMap[] cache

allCached

protected boolean[] allCached

Constructor Detail

Morphy

public Morphy(WordNet wn)

Initialize a new Morphy object for finding lemmas for instances of words or collocations.

Parameters:

wn - reference to a WordNet object

Method Detail

cacheAll

public void cacheAll()

cacheAll

public void cacheAll(String pos)

cacheAll

public void cacheAll(int posIdx)

getSuffix

protected static final String[][] getSuffix(String pos)

Gets the suffix array for a particular part of speech, either nounSuffixes, verbSuffixes or adjSuffixes.

Parameters:

pos - the part of speech

Returns:

an array of two-element String arrays

getSuffix

protected static final String[][] getSuffix(int posIdx)

Gets the suffix array for a particular part of speech, either nounSuffixes, verbSuffixes or adjSuffixes.

Parameters:

posIdx - the part of speech

Returns:

an array of two-element String arrays

countWords

public static final int countWords(String s,
                                   char separator)

Same as countWords, but with word-delimiters specifically set to separator, ' ' and '_'.

Parameters:

s - string in which to count words

separator - word-separator (in addition to ' ' and '_')

Returns:

number of words in s

countWords

public static final int countWords(String s,
                                   String delim)

Counts number of tokens in s separated by the delimiter characters specified by delim.

Parameters:

s - string in which to count words

delim - String object whose characters are treated as delimiters when finding words in s

Returns:

number of words in s

exceptionLookup

protected String[] exceptionLookup(String str,
                                   String pos)

Looks up exceptions for str in the WordNet exception file for pos

Parameters:

str - word or collocation to look up

pos - part of speech of str

Returns:

array of words found in exception list, or null if none exists

hasPrep

protected boolean hasPrep(String str)

Returns true if any word in (assumed collocated) str other than first or last contains a preposition.

Parameters:

str - collocation

containsNonAlnum

protected static boolean containsNonAlnum(String s)

Predicate for determining if any characters in s are non-alphanumeric.

Parameters:

s - the string to examine.

Returns:

true if at least one character is not a letter or digit; false otherwise.

See Also:

Character.isLetterOrDigit(char)

wordBase

protected String wordBase(String word,
                          String[][] suffixes,
                          int sufIdx)

Tries to form the base form of a word using information in a suffix lookup table.

Parameters:

word - word with possible suffix to be replaced

suffixes - suffix array: array of two-element String arrays

sufIdx - index into suffixes

Returns:

If word ends with suffixes[sufIdx][0], strips of this suffix and returns the stem concatenated with suffixes[sufIdx][1]; otherwise returns null.

morphWord

protected String morphWord(String word,
                           String pos)

Tries to find morph of a single word

Parameters:

word - word to be morphed

pos - part of speech of word to be morphed

Returns:

possible morph of word

morphPrep

protected String[] morphPrep(String str)

Tries to find morphs for str, which is assumed to be a collocation containing a verb, a preposition and a noun. Assumes str's first word is a verb and its last word a noun, with an intervening word a preposition. The following steps are tried, in this order:

1. try to morph final word if there are more than two words; save
2. if first word contains non alphanumeric chars, return null
3. return exception-list-morphed verb + rest of collocation if in WN
4. return exception-list-morphed verb + rest of collocation with morphed final word, if in WN
5. foreach possible suffix for the first word (assumed to be a verb), if a suffix is found, replace with an alternative suffix (table lookup) and try the following two things in the following order:
   1. return verb with new ending + rest of collocation, if in WN
   2. return verb with new ending + rest of collocation with morphed final word, if in WN
6. return first word + rest if different from original string (???)
7. return first word + rest of collocation with morphed final word

Parameters:

str - collocation to morph containing verb, preposition and noun

Returns:

morph of str

morphStr

public String[] morphStr(String origstr,
                         String pos)

Tries several techniques on origstr to find possible base forms (lemmas).

Specified by:

morphStr in interface MorphyRemote

Parameters:

origstr - word or collocation, separated either by whitespace, '_' or '-', to find lemma of

pos - part of speech of origstr

Returns:

array of possible lemmas for origstr, possibly of length 0 if no lemmas could be found

main

public static void main(String[] args)

Simple test driver for Morphy, reading one word/collocation per line from System.in, and spitting out possible morphs for each of the three morphable parts of speech: nouns, verbs and ajdectives.

Parameters:

args -