cc.wikitools.lucene.hadoop.SearchWikipediaHdfs.java Source code

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Here is the source code for cc.wikitools.lucene.hadoop.SearchWikipediaHdfs.java

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/**
 * wiki-tools-lucene-hadoop: Java tools for searching Wikipedia Lucene indexes in HDFS
 *
 * 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 cc.wikitools.lucene.hadoop;

import java.io.PrintStream;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.GnuParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.OptionBuilder;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.lucene.document.Document;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;

import cc.wikitools.lucene.IndexWikipediaDump.IndexField;

public class SearchWikipediaHdfs extends Configured implements Tool {
    private static final int DEFAULT_NUM_RESULTS = 10;

    private static final String INDEX_OPTION = "index";
    private static final String QUERY_OPTION = "q";
    private static final String NUM_RESULTS_OPTION = "num_results";
    private static final String VERBOSE_OPTION = "verbose";
    private static final String ARTICLE_OPTION = "article";
    private static final String TITLE_OPTION = "title";

    @SuppressWarnings("static-access")
    @Override
    public int run(String[] args) throws Exception {
        Options options = new Options();
        options.addOption(
                OptionBuilder.withArgName("path").hasArg().withDescription("index location").create(INDEX_OPTION));
        options.addOption(
                OptionBuilder.withArgName("string").hasArg().withDescription("query text").create(QUERY_OPTION));
        options.addOption(OptionBuilder.withArgName("num").hasArg().withDescription("number of results to return")
                .create(NUM_RESULTS_OPTION));

        options.addOption(new Option(VERBOSE_OPTION, "print out complete document"));
        options.addOption(new Option(TITLE_OPTION, "search title"));
        options.addOption(new Option(ARTICLE_OPTION, "search article"));

        CommandLine cmdline = null;
        CommandLineParser parser = new GnuParser();
        try {
            cmdline = parser.parse(options, args);
        } catch (ParseException exp) {
            System.err.println("Error parsing command line: " + exp.getMessage());
            System.exit(-1);
        }

        if (!cmdline.hasOption(QUERY_OPTION) || !cmdline.hasOption(INDEX_OPTION)
                || !cmdline.hasOption(QUERY_OPTION)) {
            HelpFormatter formatter = new HelpFormatter();
            formatter.printHelp(SearchWikipediaHdfs.class.getName(), options);
            System.exit(-1);
        }

        String indexLocation = cmdline.getOptionValue(INDEX_OPTION);
        String queryText = cmdline.getOptionValue(QUERY_OPTION);
        int numResults = cmdline.hasOption(NUM_RESULTS_OPTION)
                ? Integer.parseInt(cmdline.getOptionValue(NUM_RESULTS_OPTION))
                : DEFAULT_NUM_RESULTS;
        boolean verbose = cmdline.hasOption(VERBOSE_OPTION);
        boolean searchArticle = !cmdline.hasOption(TITLE_OPTION);

        PrintStream out = new PrintStream(System.out, true, "UTF-8");

        HdfsWikipediaSearcher searcher = new HdfsWikipediaSearcher(new Path(indexLocation), getConf());
        TopDocs rs = null;
        if (searchArticle) {
            rs = searcher.searchArticle(queryText, numResults);
        } else {
            rs = searcher.searchTitle(queryText, numResults);
        }

        int i = 1;
        for (ScoreDoc scoreDoc : rs.scoreDocs) {
            Document hit = searcher.doc(scoreDoc.doc);

            out.println(String.format("%d. %s (id = %s) %f", i, hit.getField(IndexField.TITLE.name).stringValue(),
                    hit.getField(IndexField.ID.name).stringValue(), scoreDoc.score));
            if (verbose) {
                out.println("# " + hit.toString().replaceAll("[\\n\\r]+", " "));
            }
            i++;
        }

        searcher.close();
        out.close();

        return 0;
    }

    public static void main(String[] args) throws Exception {
        ToolRunner.run(new SearchWikipediaHdfs(), args);
    }
}