Java tutorial
/* * Copyright (c) 2008, 2014, Oracle and/or its affiliates. * All rights reserved. Use is subject to license terms. * * This file is available and licensed under the following license: * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the distribution. * - Neither the name of Oracle Corporation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ package ensemble.search; import ensemble.generated.Samples; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.*; import javafx.application.ConditionalFeature; import javafx.application.Platform; import org.apache.lucene.analysis.Analyzer; import org.apache.lucene.analysis.standard.StandardAnalyzer; import org.apache.lucene.document.Document; import org.apache.lucene.queryParser.MultiFieldQueryParser; import org.apache.lucene.queryParser.ParseException; import org.apache.lucene.search.Query; import org.apache.lucene.search.ScoreDoc; import org.apache.lucene.search.Sort; import org.apache.lucene.search.grouping.GroupDocs; import org.apache.lucene.search.grouping.SearchGroup; import org.apache.lucene.search.grouping.SecondPassGroupingCollector; import org.apache.lucene.search.grouping.TopGroups; import org.apache.lucene.util.Version; /** * Class for searching the index */ public class IndexSearcher { private final static List<SearchGroup> searchGroups = new ArrayList<>(); static { for (DocumentType dt : DocumentType.values()) { SearchGroup searchGroup = new SearchGroup(); searchGroup.groupValue = dt.toString(); searchGroup.sortValues = new Comparable[] { 5f }; searchGroups.add(searchGroup); } } private org.apache.lucene.search.IndexSearcher searcher; private final Analyzer analyzer; private final MultiFieldQueryParser parser; public IndexSearcher() { try { searcher = new org.apache.lucene.search.IndexSearcher(new ClasspathDirectory()); } catch (IOException e) { e.printStackTrace(); } analyzer = new StandardAnalyzer(Version.LUCENE_31); parser = new MultiFieldQueryParser(Version.LUCENE_31, new String[] { "name", "bookTitle", "chapter", "description" }, analyzer); } public Map<DocumentType, List<SearchResult>> search(String searchString) throws ParseException { Map<DocumentType, List<SearchResult>> resultMap = new EnumMap<>(DocumentType.class); try { Query query = parser.parse(searchString); final SecondPassGroupingCollector collector = new SecondPassGroupingCollector("documentType", searchGroups, Sort.RELEVANCE, Sort.RELEVANCE, 10, true, false, true); searcher.search(query, collector); final TopGroups groups = collector.getTopGroups(0); for (GroupDocs groupDocs : groups.groups) { DocumentType docType = DocumentType.valueOf(groupDocs.groupValue); List<SearchResult> results = new ArrayList<>(); for (ScoreDoc scoreDoc : groupDocs.scoreDocs) { if ((Platform.isSupported(ConditionalFeature.WEB)) || (docType != DocumentType.DOC)) { Document doc = searcher.doc(scoreDoc.doc); SearchResult result = new SearchResult(docType, doc.get("name"), doc.get("url"), doc.get("className"), doc.get("package"), doc.get("ensemblePath"), docType == DocumentType.DOC ? doc.get("bookTitle") == null ? doc.get("chapter") : doc.get("bookTitle") : doc.get("shortDescription").trim()); /* If the result is a sample, then filter out the samples that * the runtime platform does not support. We really want to show * just 5 results, but we search for 10 and filter out unsupported * samples and show just 5. */ if (docType == DocumentType.SAMPLE) { if (Samples.ROOT.sampleForPath(result.getEnsemblePath().substring(9).trim()) == null) { // Skip unsupported (not existing) samples continue; } if (results.size() == 5) { // 5 samples is enough break; } } results.add(result); } } resultMap.put(docType, results); } } catch (IOException e) { e.printStackTrace(); } return resultMap; } /** * Simple command line test application * @param args command line arguments * @throws Exception for maps errors */ public static void main(String[] args) throws Exception { BufferedReader in = new BufferedReader(new InputStreamReader(System.in, "UTF-8")); IndexSearcher indexSearcher = new IndexSearcher(); while (true) { System.out.println("Enter query: "); String line = in.readLine(); if (line == null || line.length() == -1) break; line = line.trim(); if (line.length() == 0) break; Map<DocumentType, List<SearchResult>> results = indexSearcher.search(line); for (Map.Entry<DocumentType, List<SearchResult>> entry : results.entrySet()) { System.out.println("--------- " + entry.getKey() + " [" + entry.getValue().size() + "] --------------------------------"); for (SearchResult result : entry.getValue()) { System.out.println(result.toString()); } } } } }