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

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Here is the source code for cc.wikitools.lucene.hadoop.FetchWikipediaArticleHdfs.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.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 cc.wikitools.lucene.FetchWikipediaArticle;
import cc.wikitools.lucene.IndexWikipediaDump.IndexField;

public class FetchWikipediaArticleHdfs extends Configured implements Tool {
    private static final String INDEX_OPTION = "index";
    private static final String ID_OPTION = "id";
    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("num").hasArg().withDescription("id").create(ID_OPTION));
        options.addOption(
                OptionBuilder.withArgName("string").hasArg().withDescription("title").create(TITLE_OPTION));

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

        String indexLocation = cmdline.getOptionValue(INDEX_OPTION);

        HdfsWikipediaSearcher searcher = new HdfsWikipediaSearcher(new Path(indexLocation), getConf());
        PrintStream out = new PrintStream(System.out, true, "UTF-8");

        if (cmdline.hasOption(ID_OPTION)) {
            int id = Integer.parseInt(cmdline.getOptionValue(ID_OPTION));
            Document doc = searcher.getArticle(id);

            if (doc == null) {
                System.err.print("id " + id + " doesn't exist!\n");
            } else {
                out.println(doc.getField(IndexField.TEXT.name).stringValue());
            }
        } else {
            String title = cmdline.getOptionValue(TITLE_OPTION);
            Document doc = searcher.getArticle(title);

            if (doc == null) {
                System.err.print("article \"" + title + "\" doesn't exist!\n");
            } else {
                out.println(doc.getField(IndexField.TEXT.name).stringValue());
            }
        }

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

        return 0;
    }

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