Java tutorial
package javatools.webapi; /** * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * 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. */ import org.apache.lucene.analysis.Analyzer; import org.apache.lucene.analysis.standard.StandardAnalyzer; import org.apache.lucene.document.Document; import org.apache.lucene.document.Field; import org.apache.lucene.document.NumericField; import org.apache.lucene.index.IndexWriter; import org.apache.lucene.index.IndexWriterConfig.OpenMode; import org.apache.lucene.index.IndexWriterConfig; import org.apache.lucene.index.Term; import org.apache.lucene.queryParser.QueryParser; import org.apache.lucene.search.IndexSearcher; import org.apache.lucene.search.Query; import org.apache.lucene.search.ScoreDoc; import org.apache.lucene.search.TopDocs; import org.apache.lucene.store.Directory; import org.apache.lucene.store.FSDirectory; import org.apache.lucene.util.Version; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStreamReader; import java.io.StringReader; import java.util.ArrayList; import java.util.Date; import java.util.List; import javatools.administrative.D; import javatools.filehandlers.DelimitedReader; import javatools.filehandlers.DelimitedWriter; /** Index all text files under a directory. See http://lucene.apache.org/java/3_1/demo.html. */ public class LuceneIndexFiles { public static void indexDelimitedFile(String file, int indexColumn, int pathColumn, String dirIndex) { Date start = new Date(); try { if ((new File(dirIndex)).exists()) { (new File(dirIndex)).delete(); } Directory dir = FSDirectory.open(new File(dirIndex)); Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_31); IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_31, analyzer); iwc.setOpenMode(OpenMode.CREATE); // Optional: for better indexing performance, if you // are indexing many documents, increase the RAM // buffer. But if you do this, increase the max heap // size to the JVM (eg add -Xmx512m or -Xmx1g): // // iwc.setRAMBufferSizeMB(256.0); IndexWriter writer = new IndexWriter(dir, iwc); indexDocs(writer, file, indexColumn, pathColumn); // NOTE: if you want to maximize search performance, // you can optionally call optimize here. This can be // a costly operation, so generally it's only worth // it when your index is relatively static (ie you're // done adding documents to it): // // writer.optimize(); writer.close(); Date end = new Date(); System.out.println(end.getTime() - start.getTime() + " total milliseconds"); } catch (IOException e) { System.out.println(" caught a " + e.getClass() + "\n with message: " + e.getMessage()); } } public static void indexDelimitedFile(String file, int indexColumn, int[] pathColumn, String dirIndex) { Date start = new Date(); try { if ((new File(dirIndex)).exists()) { (new File(dirIndex)).delete(); } Directory dir = FSDirectory.open(new File(dirIndex)); Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_31); IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_31, analyzer); iwc.setOpenMode(OpenMode.CREATE); // Optional: for better indexing performance, if you // are indexing many documents, increase the RAM // buffer. But if you do this, increase the max heap // size to the JVM (eg add -Xmx512m or -Xmx1g): // // iwc.setRAMBufferSizeMB(256.0); IndexWriter writer = new IndexWriter(dir, iwc); indexDocs(writer, file, indexColumn, pathColumn); // NOTE: if you want to maximize search performance, // you can optionally call optimize here. This can be // a costly operation, so generally it's only worth // it when your index is relatively static (ie you're // done adding documents to it): // // writer.optimize(); writer.close(); Date end = new Date(); System.out.println(end.getTime() - start.getTime() + " total milliseconds"); } catch (IOException e) { System.out.println(" caught a " + e.getClass() + "\n with message: " + e.getMessage()); } } public static void indexDelimitedFile(String file, int[] indexColumn, int[] pathColumn, String dirIndex) { Date start = new Date(); try { if ((new File(dirIndex)).exists()) { (new File(dirIndex)).delete(); } Directory dir = FSDirectory.open(new File(dirIndex)); Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_31); IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_31, analyzer); iwc.setOpenMode(OpenMode.CREATE); // Optional: for better indexing performance, if you // are indexing many documents, increase the RAM // buffer. But if you do this, increase the max heap // size to the JVM (eg add -Xmx512m or -Xmx1g): // // iwc.setRAMBufferSizeMB(256.0); IndexWriter writer = new IndexWriter(dir, iwc); indexDocs(writer, file, indexColumn, pathColumn); // NOTE: if you want to maximize search performance, // you can optionally call optimize here. This can be // a costly operation, so generally it's only worth // it when your index is relatively static (ie you're // done adding documents to it): // // writer.optimize(); writer.close(); Date end = new Date(); System.out.println(end.getTime() - start.getTime() + " total milliseconds"); } catch (IOException e) { System.out.println(" caught a " + e.getClass() + "\n with message: " + e.getMessage()); } } public static void main(String[] args) { // indexDelimitedFile } /** Index all text files under a directory. */ public static void main2(String[] args) { String usage = "java org.apache.lucene.demo.IndexFiles" + " [-index INDEX_PATH] [-docs DOCS_PATH] [-update]\n\n" // TODO: Change the link with every release (or: fill in some less error-prone alternative here...) + "See http://lucene.apache.org/java/3_1/demo.html for details."; String indexPath = "index"; String docsPath = null; boolean create = true; for (int i = 0; i < args.length; i++) { if ("-index".equals(args[i])) { indexPath = args[i + 1]; i++; } else if ("-docs".equals(args[i])) { docsPath = args[i + 1]; i++; } else if ("-update".equals(args[i])) { create = false; } } if (docsPath == null) { System.err.println("Usage: " + usage); System.exit(1); } final File docDir = new File(docsPath); if (!docDir.exists() || !docDir.canRead()) { System.out.println("Document directory '" + docDir.getAbsolutePath() + "' does not exist or is not readable, please check the path"); System.exit(1); } Date start = new Date(); try { System.out.println("Indexing to directory '" + indexPath + "'..."); Directory dir = FSDirectory.open(new File(indexPath)); Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_31); IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_31, analyzer); if (create) { // Create a new index in the directory, removing any // previously indexed documents: iwc.setOpenMode(OpenMode.CREATE); } else { // Add new documents to an existing index: iwc.setOpenMode(OpenMode.CREATE_OR_APPEND); } // Optional: for better indexing performance, if you // are indexing many documents, increase the RAM // buffer. But if you do this, increase the max heap // size to the JVM (eg add -Xmx512m or -Xmx1g): // // iwc.setRAMBufferSizeMB(256.0); IndexWriter writer = new IndexWriter(dir, iwc); indexDocs(writer, docDir); // NOTE: if you want to maximize search performance, // you can optionally call optimize here. This can be // a costly operation, so generally it's only worth // it when your index is relatively static (ie you're // done adding documents to it): // // writer.optimize(); writer.close(); Date end = new Date(); System.out.println(end.getTime() - start.getTime() + " total milliseconds"); } catch (IOException e) { System.out.println(" caught a " + e.getClass() + "\n with message: " + e.getMessage()); } } /** * Indexes the given file using the given writer, or if a directory is given, * recurses over files and directories found under the given directory. * * NOTE: This method indexes one document per input file. This is slow. For good * throughput, put multiple documents into your input file(s). An example of this is * in the benchmark module, which can create "line doc" files, one document per line, * using the * <a href="../../../../../contrib-benchmark/org/apache/lucene/benchmark/byTask/tasks/WriteLineDocTask.html" * >WriteLineDocTask</a>. * * @param writer Writer to the index where the given file/dir info will be stored * @param file The file to index, or the directory to recurse into to find files to index * @throws IOException */ static void indexDocs(IndexWriter writer, File file) throws IOException { // do not try to index files that cannot be read if (file.canRead()) { if (file.isDirectory()) { String[] files = file.list(); // an IO error could occur if (files != null) { for (int i = 0; i < files.length; i++) { indexDocs(writer, new File(file, files[i])); } } } else { FileInputStream fis; try { fis = new FileInputStream(file); } catch (FileNotFoundException fnfe) { // at least on windows, some temporary files raise this exception with an "access denied" message // checking if the file can be read doesn't help return; } try { // make a new, empty document Document doc = new Document(); // Add the path of the file as a field named "path". Use a // field that is indexed (i.e. searchable), but don't tokenize // the field into separate words and don't index term frequency // or positional information: Field pathField = new Field("path", file.getPath(), Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS); pathField.setOmitTermFreqAndPositions(true); doc.add(pathField); // Add the last modified date of the file a field named "modified". // Use a NumericField that is indexed (i.e. efficiently filterable with // NumericRangeFilter). This indexes to milli-second resolution, which // is often too fine. You could instead create a number based on // year/month/day/hour/minutes/seconds, down the resolution you require. // For example the long value 2011021714 would mean // February 17, 2011, 2-3 PM. NumericField modifiedField = new NumericField("modified"); modifiedField.setLongValue(file.lastModified()); doc.add(modifiedField); // Add the contents of the file to a field named "contents". Specify a Reader, // so that the text of the file is tokenized and indexed, but not stored. // Note that FileReader expects the file to be in UTF-8 encoding. // If that's not the case searching for special characters will fail. doc.add(new Field("contents", new BufferedReader(new InputStreamReader(fis, "UTF-8")))); if (writer.getConfig().getOpenMode() == OpenMode.CREATE) { // New index, so we just add the document (no old document can be there): System.out.println("adding " + file); writer.addDocument(doc); } else { // Existing index (an old copy of this document may have been indexed) so // we use updateDocument instead to replace the old one matching the exact // path, if present: System.out.println("updating " + file); writer.updateDocument(new Term("path", file.getPath()), doc); } } finally { fis.close(); } } } } static void indexDocs(IndexWriter writer, String file, int indexColumn, int pathColumn) throws IOException { DelimitedReader dr = new DelimitedReader(file); String[] l; while ((l = dr.read()) != null) { Document doc = new Document(); String path = l[pathColumn]; Field pathField = new Field("path", path, Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS); pathField.setOmitTermFreqAndPositions(true); doc.add(pathField); doc.add(new Field("contents", new StringReader(l[indexColumn]))); writer.addDocument(doc); } dr.close(); } static void indexDocs(IndexWriter writer, String file, int indexColumn, int[] pathColumn) throws IOException { DelimitedReader dr = new DelimitedReader(file); String[] l; int count = 0; while ((l = dr.read()) != null) { // if (count++ > 10000) // break; Document doc = new Document(); StringBuilder sbp = new StringBuilder(); for (int a : pathColumn) { String path = l[a]; sbp.append(path).append("\t"); } Field pathField = new Field("path", sbp.toString(), Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS); pathField.setOmitTermFreqAndPositions(true); doc.add(pathField); //doc.add(new Field("contents", new StringReader(l[indexColumn]))); doc.add(new Field("contents", l[indexColumn], Field.Store.YES, Field.Index.ANALYZED)); writer.addDocument(doc); } dr.close(); } static void indexDocs(IndexWriter writer, String file, int[] indexColumn, int[] pathColumn) throws IOException { DelimitedReader dr = new DelimitedReader(file); String[] l; int count = 0; while ((l = dr.read()) != null) { // if (count++ > 10000) // break; Document doc = new Document(); StringBuilder sbp = new StringBuilder(); for (int a : pathColumn) { String path = l[a]; sbp.append(path).append("\t"); } Field pathField = new Field("path", sbp.toString(), Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS); pathField.setOmitTermFreqAndPositions(true); doc.add(pathField); //doc.add(new Field("contents", new StringReader(l[indexColumn]))); StringBuilder sb = new StringBuilder(); for (int x : indexColumn) { sb.append(l[x] + " "); } doc.add(new Field("contents", sb.toString(), Field.Store.YES, Field.Index.ANALYZED)); writer.addDocument(doc); } dr.close(); } public static void searchDelimitedFile(String dirIndex, List<String> list_query, String output) { String index = dirIndex; String field = "contents"; String queries = null; int repeat = 0; boolean raw = false; String queryString = null; int hitsPerPage = 10; try { DelimitedWriter dw = new DelimitedWriter(output); IndexSearcher searcher = new IndexSearcher(FSDirectory.open(new File(index))); Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_31); QueryParser parser = new QueryParser(Version.LUCENE_31, field, analyzer); for (String line : list_query) { Query query = parser.parse(line); System.out.println("Searching for: " + query.toString(field)); if (repeat > 0) { // repeat & time as benchmark Date start = new Date(); for (int i = 0; i < repeat; i++) { searcher.search(query, null, 100); } Date end = new Date(); System.out.println("Time: " + (end.getTime() - start.getTime()) + "ms"); } List<String[]> results = doPagingSearch2(searcher, query, hitsPerPage); for (String[] r : results) { String[] ab = r[0].split("\t"); dw.write(line, ab[0], ab[1], ab[2], r[1]); } //doPagingSearch2(in, searcher, query, hitsPerPage, raw, queries == null && queryString == null); } dw.close(); } catch (Exception e) { e.printStackTrace(); } } /** Simple command-line based search demo. */ public static void main_search(String[] args) throws Exception { String usage = "Usage:\tjava org.apache.lucene.demo.SearchFiles [-index dir] [-field f] [-repeat n] [-queries file] [-query string] [-raw] [-paging hitsPerPage]\n\nSee http://lucene.apache.org/java/4_0/demo.html for details."; if (args.length > 0 && ("-h".equals(args[0]) || "-help".equals(args[0]))) { System.out.println(usage); System.exit(0); } String index = "index"; String field = "contents"; String queries = null; int repeat = 0; boolean raw = false; String queryString = null; int hitsPerPage = 10; for (int i = 0; i < args.length; i++) { if ("-index".equals(args[i])) { index = args[i + 1]; i++; } else if ("-field".equals(args[i])) { field = args[i + 1]; i++; } else if ("-queries".equals(args[i])) { queries = args[i + 1]; i++; } else if ("-query".equals(args[i])) { queryString = args[i + 1]; i++; } else if ("-repeat".equals(args[i])) { repeat = Integer.parseInt(args[i + 1]); i++; } else if ("-raw".equals(args[i])) { raw = true; } else if ("-paging".equals(args[i])) { hitsPerPage = Integer.parseInt(args[i + 1]); if (hitsPerPage <= 0) { System.err.println("There must be at least 1 hit per page."); System.exit(1); } i++; } } IndexSearcher searcher = new IndexSearcher(FSDirectory.open(new File(index))); Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_31); BufferedReader in = null; if (queries != null) { in = new BufferedReader(new InputStreamReader(new FileInputStream(queries), "UTF-8")); } else { in = new BufferedReader(new InputStreamReader(System.in, "UTF-8")); } QueryParser parser = new QueryParser(Version.LUCENE_31, field, analyzer); while (true) { if (queries == null && queryString == null) { // prompt the user System.out.println("Enter query: "); } String line = queryString != null ? queryString : in.readLine(); if (line == null || line.length() == -1) { break; } line = line.trim(); if (line.length() == 0) { break; } Query query = parser.parse(line); System.out.println("Searching for: " + query.toString(field)); if (repeat > 0) { // repeat & time as benchmark Date start = new Date(); for (int i = 0; i < repeat; i++) { searcher.search(query, null, 100); } Date end = new Date(); System.out.println("Time: " + (end.getTime() - start.getTime()) + "ms"); } doPagingSearch(in, searcher, query, hitsPerPage, raw, queries == null && queryString == null); if (queryString != null) { break; } } searcher.close(); } /** * This demonstrates a typical paging search scenario, where the search engine presents * pages of size n to the user. The user can then go to the next page if interested in * the next hits. * * When the query is executed for the first time, then only enough results are collected * to fill 5 result pages. If the user wants to page beyond this limit, then the query * is executed another time and all hits are collected. * */ public static void doPagingSearch(BufferedReader in, IndexSearcher searcher, Query query, int hitsPerPage, boolean raw, boolean interactive) throws IOException { // Collect enough docs to show 5 pages TopDocs results = searcher.search(query, 5 * hitsPerPage); ScoreDoc[] hits = results.scoreDocs; int numTotalHits = results.totalHits; System.out.println(numTotalHits + " total matching documents"); int start = 0; int end = Math.min(numTotalHits, hitsPerPage); while (true) { if (end > hits.length) { System.out.println("Only results 1 - " + hits.length + " of " + numTotalHits + " total matching documents collected."); System.out.println("Collect more (y/n) ?"); String line = in.readLine(); if (line.length() == 0 || line.charAt(0) == 'n') { break; } hits = searcher.search(query, numTotalHits).scoreDocs; } end = Math.min(hits.length, start + hitsPerPage); for (int i = start; i < end; i++) { if (raw) { // output raw format System.out.println("doc=" + hits[i].doc + " score=" + hits[i].score); continue; } Document doc = searcher.doc(hits[i].doc); String path = doc.get("path"); if (path != null) { System.out.println((i + 1) + ". " + path); String title = doc.get("title"); if (title != null) { System.out.println(" Title: " + doc.get("title")); } } else { System.out.println((i + 1) + ". " + "No path for this document"); } } if (!interactive || end == 0) { break; } if (numTotalHits >= end) { boolean quit = false; while (true) { System.out.print("Press "); if (start - hitsPerPage >= 0) { System.out.print("(p)revious page, "); } if (start + hitsPerPage < numTotalHits) { System.out.print("(n)ext page, "); } System.out.println("(q)uit or enter number to jump to a page."); String line = in.readLine(); if (line.length() == 0 || line.charAt(0) == 'q') { quit = true; break; } if (line.charAt(0) == 'p') { start = Math.max(0, start - hitsPerPage); break; } else if (line.charAt(0) == 'n') { if (start + hitsPerPage < numTotalHits) { start += hitsPerPage; } break; } else { int page = Integer.parseInt(line); if ((page - 1) * hitsPerPage < numTotalHits) { start = (page - 1) * hitsPerPage; break; } else { System.out.println("No such page"); } } } if (quit) break; end = Math.min(numTotalHits, start + hitsPerPage); } } } public static List<String[]> doPagingSearch2(IndexSearcher searcher, Query query, int hitsPerPage) throws IOException { List<String[]> searchresult = new ArrayList<String[]>(); // Collect enough docs to show 5 pages TopDocs results = searcher.search(query, 10 * hitsPerPage); ScoreDoc[] hits = results.scoreDocs; int numTotalHits = results.totalHits; System.out.println(numTotalHits + " total matching documents"); int start = 0; int end = Math.min(numTotalHits, hitsPerPage); for (int i = 0; i < numTotalHits && i < hits.length; i++) { { Document doc = searcher.doc(hits[i].doc); String path = doc.get("path"); if (path != null) { //System.out.println((i + 1) + ". " + path); String contents = doc.get("contents"); searchresult.add(new String[] { path, contents }); if (contents != null) { //System.out.println(" Contents: " + contents); } } else { //System.out.println((i + 1) + ". " + "No path for this document"); } } } return searchresult; } }