app.finder.topicsource.service.SearchFiles.java Source code

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Here is the source code for app.finder.topicsource.service.SearchFiles.java

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package app.finder.topicsource.service;

/*
 * 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 java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.queryparser.classic.ParseException;
import org.apache.lucene.queryparser.classic.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.FSDirectory;

import app.finder.topicsource.model.TopicSource;

/** Simple command-line based search demo. */
public class SearchFiles {

    private static final int SEARCH_MAX_SIZE = 1000;
    // private static final INDEX_DIR =
    // "/Users/rene/learn/learn5/lucene/finder/index";
    private String indexDir;

    public SearchFiles(String indexDir) {
        this.indexDir = indexDir;
    }

    public List<TopicSource> getTopicSources(String queryString) throws IOException, ParseException {
        String field = "contents";
        String queries = null;
        int repeat = 0;
        boolean raw = false;

        int hitsPerPage = SEARCH_MAX_SIZE; // 100;
        IndexReader reader = DirectoryReader.open(FSDirectory.open(Paths.get(indexDir)));
        IndexSearcher searcher = new IndexSearcher(reader);
        Analyzer analyzer = new StandardAnalyzer();

        BufferedReader in = null;
        QueryParser parser = new QueryParser(field, analyzer);

        Query query = parser.parse(queryString);

        //System.out.println("Searching for: " + query.toString(field));
        searcher.search(query, null, SEARCH_MAX_SIZE);

        List<String> list = doSearch(in, searcher, query, hitsPerPage, raw, queries == null && queryString == null);

        reader.close();

        List<TopicSource> topicSourceList = new ArrayList<TopicSource>();
        TopicSource topicSource = null;
        int counter = 0;
        for (String fileName : list) {
            topicSource = new TopicSource();
            File file = new File(fileName);

            topicSource.setFileName("" + (++counter) + ". " + file.getName());
            topicSource.setPath(file.getCanonicalPath());
            topicSource.setText(readFile(file));
            topicSourceList.add(topicSource);
        }

        return topicSourceList;
    }

    private String readFile(File file) throws IOException {

        StringBuffer sb = new StringBuffer();

        BufferedReader reader = new BufferedReader(new FileReader(file));

        String sCurrentLine;
        while ((sCurrentLine = reader.readLine()) != null) {
            sb.append(sCurrentLine + "\n");
        }

        return sb.toString();
    }

    //   /** Simple command-line based search demo. */
    //   public static void main(String[] args) throws Exception {
    //      
    //
    //      String index = "/Users/rene/learn/topic-index"; //"/Users/rene/learn/learn5/lucene/finder/index";
    //      
    //      SearchFiles searchFiles = new SearchFiles(index);
    //      
    //      List<TopicSource> list = searchFiles.getTopicSources("viewresolver");
    //      
    //      int counter = 0;
    //      for (TopicSource topicSource: list) {
    //         System.out.println("" + (++counter) + ". -----------------------FileName: " + topicSource.getPath());
    //         System.out.println(topicSource.getText());
    //      }
    //      
    //       
    //   }

    /**
     * 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 List<String> doSearch(BufferedReader in, IndexSearcher searcher, Query query, int hitsPerPage,
            boolean raw, boolean interactive) throws IOException {

        List<String> list = new ArrayList<String>();

        // 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);

        for (int i = start; i < end; i++) {
            Document doc = searcher.doc(hits[i].doc);
            String path = doc.get("path");
            if (path != null) {

                //System.out.println((i + 1) + ". " + path);

                list.add(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.");
            }

        }

        return list;
    }
}