Java tutorial
/** * wiki-tools-lucene: Java package for searching Wikipedia dumps with Lucene * * 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; import java.io.File; 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.lucene.document.Document; import cc.wikitools.lucene.IndexWikipediaDump.IndexField; public class FetchWikipediaArticle { private static final String INDEX_OPTION = "index"; private static final String ID_OPTION = "id"; private static final String TITLE_OPTION = "title"; @SuppressWarnings("static-access") public static void main(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("article id").create(ID_OPTION)); options.addOption( OptionBuilder.withArgName("string").hasArg().withDescription("article 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); } File indexLocation = new File(cmdline.getOptionValue(INDEX_OPTION)); if (!indexLocation.exists()) { System.err.println("Error: " + indexLocation + " does not exist!"); System.exit(-1); } WikipediaSearcher searcher = new WikipediaSearcher(indexLocation); 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(); } }