uk.ac.ebi.arrayexpress.utils.saxon.search.QueryHighlighter.java Source code

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Here is the source code for uk.ac.ebi.arrayexpress.utils.saxon.search.QueryHighlighter.java

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package uk.ac.ebi.arrayexpress.utils.saxon.search;

/*
 * Copyright 2009-2011 European Molecular Biology Laboratory
 *
 * 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.
 *
 */

import org.apache.lucene.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.NullFragmenter;
import org.apache.lucene.search.highlight.QueryScorer;
import org.apache.lucene.search.highlight.SimpleHTMLFormatter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class QueryHighlighter implements IQueryHighlighter {
    // logging machinery
    private final Logger logger = LoggerFactory.getLogger(getClass());

    private AbstractIndexEnvironment env;

    private static final String HIT_OPEN_MARK = "\u00ab";
    private static final String HIT_CLOSE_MARK = "\u00bb";

    public IQueryHighlighter setEnvironment(AbstractIndexEnvironment env) {
        this.env = env;
        return this;
    }

    public String highlightQuery(QueryInfo queryInfo, String fieldName, String text) {
        try {
            SimpleHTMLFormatter htmlFormatter = new SimpleHTMLFormatter(HIT_OPEN_MARK, HIT_CLOSE_MARK);
            Highlighter highlighter = new Highlighter(htmlFormatter,
                    new QueryScorer(queryInfo.getQuery(), fieldName, this.env.defaultField));
            highlighter.setTextFragmenter(new NullFragmenter());

            String str = highlighter.getBestFragment(this.env.indexAnalyzer,
                    "".equals(fieldName) ? this.env.defaultField : fieldName, text);

            return null != str ? str : text;
        } catch (Exception x) {
            logger.error("Caught an exception:", x);
        }
        return text;
    }
}