porterstemmerwrapper.java

这是某个老师编写的JAVA编程软件包

  /*
  WVTool - Word Vector Tool
  Copyright (C) 2001-2007

	    Michael Wurst       

  web:   http://wvtool.sourceforge.net

  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as 
  published by the Free Software Foundation; either version 2 of the
  License, or (at your option) any later version. 

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  USA.
*/
package edu.udo.cs.wvtool.generic.stemmer;

import edu.udo.cs.wvtool.external.Stemmer;

/**
 * Wrapper for the Porter Stemmer provided with the system.
 * 
 * @author Michael Wurst
 * @version $Id: PorterStemmerWrapper.java,v 1.3 2007/05/20 18:06:02 mjwurst Exp $
 * 
 */
public class PorterStemmerWrapper extends AbstractStemmer {

    /** the stemmer itself */
    private final Stemmer stemmer;

    public PorterStemmerWrapper() {

        super();

        stemmer = new Stemmer();
    }

    public String getBase(String s) {
        if (s != null) {
            s = s.toLowerCase();
            int length = s.length();
            char[] ch = new char[length];
            s.getChars(0, length, ch, 0);
            stemmer.add(ch, length);
            stemmer.stem();
            char[] result = stemmer.getResultBuffer();
            return new String(result, 0, stemmer.getResultLength());
        } else
            return null;

    }

}