StemFilterWrap.java

/*
* Copyright 2010 Bizosys Technologies Limited
*
* Licensed to the Bizosys Technologies Limited (Bizosys) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The Bizosys licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License.  You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.bizosys.hsearch.inpipe.util;

import java.io.IOException;

import org.apache.lucene.analysis.TokenFilter;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;

import com.bizosys.hsearch.lang.Stemmer;

/**
 * Wrapped stemmed filter
 * @author karan
 *
 */
public class StemFilterWrap extends TokenFilter {

	private Stemmer stemmer;
	private CharTermAttribute termA = null; 
	

	public StemFilterWrap(TokenStream in) {
		super(in);
		stemmer = Stemmer.getInstance();
		this.termA = (CharTermAttribute)in.getAttribute(CharTermAttribute.class);;
	}
	
	public final boolean incrementToken() throws IOException {
		boolean isIncremented = input.incrementToken();
		if ( ! isIncremented ) return isIncremented;
		
		 if (termA != null) {
			 String stemWord = stemmer.stem(termA.toString());
			 this.termA.copyBuffer(stemWord.toCharArray(),0,stemWord.length());
		}
		 return isIncremented;
	}
	
	
}