org.egothor.parser.filter

Class Stemmer

java.lang.Object

org.egothor.core.Filter

org.egothor.parser.filter.Stemmer

All Implemented Interfaces:

Sequence<Token>

public final class Stemmer
extends Filter

The Stemmer object is a filter which transforms all words to their respective stems.

Author:

Leo Galambos

Field Summary

Fields inherited from class org.egothor.core.Filter

prev

Constructor Summary

Constructors

Constructor and Description
Stemmer(Sequence<Token> prev, Trie stemmer) Construct a Stem object using the given stemmer table.

Method Summary

Modifier and Type	Method and Description
Token	action(Token t) A simple stemming algorithm which works as follows:
void	setStemmer(Trie stemmer) Sets the stemmer attribute of the Stem object

Methods inherited from class org.egothor.core.Filter

getPrevTokenizer, next, setPrevTokenizer

Methods inherited from class java.lang.Object

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

Constructor Detail

Stemmer

public Stemmer(Sequence<Token> prev,
               Trie stemmer)

Construct a Stem object using the given stemmer table.

Parameters:

prev - this filter's Tokenizer

stemmer - the stemmer table

Method Detail

setStemmer

public void setStemmer(Trie stemmer)

Sets the stemmer attribute of the Stem object

Parameters:

stemmer - The new stemmer value

action

public Token action(Token t)

A simple stemming algorithm which works as follows:

If the token is <WORD>, and the text of the token is longer than 4 characters, then the token's text is transformed to its stem. The transformation will not be done when the stem is shorter than three characters.

Overrides:

action in class Filter

Parameters:

t - the Token

Returns:

the transformed Token