Java tutorial
/** * Twitter Tools * * 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.twittertools.search.local; 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.Option; 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 org.apache.lucene.index.DirectoryReader; import org.apache.lucene.index.IndexReader; import org.apache.lucene.queryparser.classic.QueryParser; import org.apache.lucene.search.Filter; import org.apache.lucene.search.IndexSearcher; import org.apache.lucene.search.NumericRangeFilter; import org.apache.lucene.search.Query; import org.apache.lucene.search.ScoreDoc; import org.apache.lucene.search.TopDocs; import org.apache.lucene.search.similarities.BM25Similarity; import org.apache.lucene.search.similarities.LMDirichletSimilarity; import org.apache.lucene.store.FSDirectory; import org.apache.lucene.util.Version; import cc.twittertools.index.IndexStatuses; import cc.twittertools.index.IndexStatuses.StatusField; /** * Reference implementation for searching statuses. */ public class SearchStatuses { private SearchStatuses() { } // Defaults: if user doesn't specify an actual query, run MB01 as a demo. private static final String DEFAULT_QID = "MB01"; private static final String DEFAULT_Q = "BBC World Service staff cuts"; private static final long DEFAULT_MAX_ID = 34952194402811905L; private static final int DEFAULT_NUM_RESULTS = 10; private static final String DEFAULT_RUNTAG = "lucene4lm"; private static final String INDEX_OPTION = "index"; private static final String QID_OPTION = "qid"; private static final String QUERY_OPTION = "q"; private static final String RUNTAG_OPTION = "runtag"; private static final String MAX_ID_OPTION = "max_id"; private static final String NUM_RESULTS_OPTION = "num_results"; private static final String SIMILARITY_OPTION = "similarity"; private static final String VERBOSE_OPTION = "verbose"; @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("string").hasArg().withDescription("query id").create(QID_OPTION)); options.addOption( OptionBuilder.withArgName("string").hasArg().withDescription("query text").create(QUERY_OPTION)); options.addOption( OptionBuilder.withArgName("string").hasArg().withDescription("runtag").create(RUNTAG_OPTION)); options.addOption(OptionBuilder.withArgName("num").hasArg().withDescription("maxid").create(MAX_ID_OPTION)); options.addOption(OptionBuilder.withArgName("num").hasArg().withDescription("number of results to return") .create(NUM_RESULTS_OPTION)); options.addOption(OptionBuilder.withArgName("similarity").hasArg() .withDescription("similarity to use (BM25, LM)").create(SIMILARITY_OPTION)); options.addOption(new Option(VERBOSE_OPTION, "print out complete document")); 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)) { HelpFormatter formatter = new HelpFormatter(); formatter.printHelp(SearchStatuses.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); } String qid = cmdline.hasOption(QID_OPTION) ? cmdline.getOptionValue(QID_OPTION) : DEFAULT_QID; String queryText = cmdline.hasOption(QUERY_OPTION) ? cmdline.getOptionValue(QUERY_OPTION) : DEFAULT_Q; String runtag = cmdline.hasOption(RUNTAG_OPTION) ? cmdline.getOptionValue(RUNTAG_OPTION) : DEFAULT_RUNTAG; long maxId = cmdline.hasOption(MAX_ID_OPTION) ? Long.parseLong(cmdline.getOptionValue(MAX_ID_OPTION)) : DEFAULT_MAX_ID; int numResults = cmdline.hasOption(NUM_RESULTS_OPTION) ? Integer.parseInt(cmdline.getOptionValue(NUM_RESULTS_OPTION)) : DEFAULT_NUM_RESULTS; boolean verbose = cmdline.hasOption(VERBOSE_OPTION); String similarity = "LM"; if (cmdline.hasOption(SIMILARITY_OPTION)) { similarity = cmdline.getOptionValue(SIMILARITY_OPTION); } PrintStream out = new PrintStream(System.out, true, "UTF-8"); IndexReader reader = DirectoryReader.open(FSDirectory.open(indexLocation)); IndexSearcher searcher = new IndexSearcher(reader); if (similarity.equalsIgnoreCase("BM25")) { searcher.setSimilarity(new BM25Similarity()); } else if (similarity.equalsIgnoreCase("LM")) { searcher.setSimilarity(new LMDirichletSimilarity(2500.0f)); } QueryParser p = new QueryParser(Version.LUCENE_43, IndexStatuses.StatusField.TEXT.name, IndexStatuses.ANALYZER); Query query = p.parse(queryText); Filter filter = NumericRangeFilter.newLongRange(StatusField.ID.name, 0L, maxId, true, true); TopDocs rs = searcher.search(query, filter, numResults); int i = 1; for (ScoreDoc scoreDoc : rs.scoreDocs) { Document hit = searcher.doc(scoreDoc.doc); out.println(String.format("%s Q0 %s %d %f %s", qid, hit.getField(StatusField.ID.name).numericValue(), i, scoreDoc.score, runtag)); if (verbose) { out.println("# " + hit.toString().replaceAll("[\\n\\r]+", " ")); } i++; } reader.close(); out.close(); } }