framework.retrieval.engine.query.formatter.impl.HighlighterMaker.java Source code

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Here is the source code for framework.retrieval.engine.query.formatter.impl.HighlighterMaker.java

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/**
 * Copyright 2010 
 *
 * Licensed 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 framework.retrieval.engine.query.formatter.impl;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.highlight.Formatter;
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 framework.retrieval.engine.query.RetrievalQueryException;
import framework.retrieval.engine.query.formatter.IHighlighterMaker;

/**
 * ?
 * @author 
 *
 */
public class HighlighterMaker implements IHighlighterMaker {
    private String htmlPrefix = "<span><font color=red>";
    private String htmlSuffix = "</font></span>";
    private Analyzer analyzer = null;

    public Analyzer getAnalyzer() {
        return analyzer;
    }

    public void setAnalyzer(Analyzer analyzer) {
        this.analyzer = analyzer;
    }

    public String getHtmlPrefix() {
        return htmlPrefix;
    }

    public void setHtmlPrefix(String htmlPrefix) {
        this.htmlPrefix = htmlPrefix;
    }

    public String getHtmlSuffix() {
        return htmlSuffix;
    }

    public void setHtmlSuffix(String htmlSuffix) {
        this.htmlSuffix = htmlSuffix;
    }

    public Formatter getFormatter() {
        return getFormatter(htmlPrefix, htmlSuffix);
    }

    private Formatter getFormatter(String htmlPrefix, String htmlSuffix) {
        SimpleHTMLFormatter simpleHTMLFormatter = new SimpleHTMLFormatter(htmlPrefix, htmlSuffix);
        return simpleHTMLFormatter;
    }

    public String getHighlighter(Query query, String fieldName, String keyWord, int resumeLength) {

        QueryScorer scorer = new QueryScorer(query);

        Highlighter highlighter = new Highlighter(getFormatter(), scorer);

        Fragmenter fragmenter = new SimpleFragmenter(resumeLength);
        highlighter.setTextFragmenter(fragmenter);

        String result = "";

        try {
            result = highlighter.getBestFragment(analyzer, fieldName, keyWord);
        } catch (Exception e) {
            throw new RetrievalQueryException(e);
        }

        return result;
    }

}