edu.coeia.util.TextHighlighter.java Source code

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Here is the source code for edu.coeia.util.TextHighlighter.java
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/* 
 * Copyright (C) 2014 Center of Excellence in Information Assurance
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */
package edu.coeia.util;

/**
 *
 * @author wajdyessam
 */

import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.highlight.Fragmenter;
import org.apache.lucene.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.QueryScorer;
import org.apache.lucene.search.highlight.SimpleFragmenter;
import org.apache.lucene.search.highlight.SimpleHTMLFormatter;

import java.io.IOException;
import java.io.StringReader;
import org.apache.lucene.util.Version;

public class TextHighlighter {
    public static String getHighlightString(String text, String keyword) throws IOException {
        TermQuery query = new TermQuery(new Term("f", keyword));
        QueryScorer scorer = new QueryScorer(query);
        SimpleHTMLFormatter formatter = new SimpleHTMLFormatter("<span class=\"highlight\">", "</span>");
        Highlighter highlighter = new Highlighter(formatter, scorer);
        Fragmenter fragmenter = new SimpleFragmenter(50);
        highlighter.setTextFragmenter(fragmenter);
        TokenStream tokenStream = new StandardAnalyzer(Version.LUCENE_20).tokenStream("f", new StringReader(text));
        //String result = highlighter.getBestFragments(tokenStream, text, 30, "...");

        StringBuilder writer = new StringBuilder("");
        writer.append("<html>");
        writer.append("<style>\n" + ".highlight {\n" + " background: yellow;\n" + "}\n" + "</style>");
        writer.append("<body>");
        writer.append("");
        writer.append("</body></html>");

        return (writer.toString());
    }

    /* lucene 3
        public static String highlightHTML(String htmlText, Query query) {
    QueryScorer scorer =  new QueryScorer(query, FIELD_NAME, FIELD_NAME);
    SimpleHTMLFormatter htmlFormatter = new SimpleHTMLFormatter("\">", "");
    Highlighter highlighter = new Highlighter(htmlFormatter, scorer);
        
    // Nullfragmenter for highlighting entire document.
    highlighter.setTextFragmenter(new NullFragmenter());
    TokenStream ts = analyzer.tokenStream(FIELD_NAME, new HTMLStripReader(new StringReader(htmlText)));
        
    try {
        String highlightedText = highlighter.getBestFragment(ts, htmlText);
        if (highlightedText != null) {
            return highlightedText;
        }
    }
    catch (Exception e) {
        e.printStackTrace();
    }
        
    return htmlText;
        }
     *
     */
}