org.tightblog.service.indexer.AbstractTask.java Source code

Introduction

Here is the source code for org.tightblog.service.indexer.AbstractTask.java

Source

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  The ASF 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.  For additional information regarding
 * copyright in this work, please see the NOTICE file in the top level
 * directory of this distribution.
 *
 * Source file modified from the original ASF source; all changes made
 * are also under Apache License.
 */
package org.tightblog.service.indexer;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
import org.apache.lucene.index.Term;
import org.tightblog.service.LuceneIndexer;

import java.io.IOException;
import java.io.StringReader;

/**
 * This is the base class for all indexing tasks, reading and writing.
 */
public abstract class AbstractTask implements Runnable {

    protected LuceneIndexer manager;

    AbstractTask(LuceneIndexer manager) {
        this.manager = manager;
    }

    @Override
    public void run() {
        doRun();
    }

    protected abstract void doRun();

    /**
     * Create a lucene term from the first token of the input string.
     *
     * @param field The lucene document field to create a term with
     * @param input The input you wish to convert into a term
     * @return Lucene search term
     */
    Term getTerm(String field, String input) {
        Term term = null;

        if (input != null && field != null) {
            try (Analyzer analyzer = manager.getAnalyzer()) {
                if (analyzer != null) {
                    try {
                        TokenStream tokens = analyzer.tokenStream(field, new StringReader(input));
                        CharTermAttribute termAtt = tokens.addAttribute(CharTermAttribute.class);
                        tokens.reset();

                        if (tokens.incrementToken()) {
                            String termt = termAtt.toString();
                            term = new Term(field, termt);
                        }
                    } catch (IOException e) {
                        // ignored
                    }
                }
            }
        }
        return term;
    }
}