concurrency.SearchFiles.java Source code

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Here is the source code for concurrency.SearchFiles.java

Source

package concurrency;

/*
 * 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.IOException;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Date;

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.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;

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

    private SearchFiles() {
    }

    /** Simple command-line based search demo. */
    public static void main(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/core/4_1_0/demo/ for details.";
        if (args.length > 0 && ("-h".equals(args[0]) || "-help".equals(args[0]))) {
            System.out.println(usage);
            System.exit(0);
        }

        String index = "/Users/rene/learn/topic-index"; //"/Users/rene/learn/learn5/lucene/finder/index";
        String field = "contents";
        String queries = null;
        int repeat = 0;
        boolean raw = false;
        // regular search
        // String queryString = "computer";

        String queryString = "viewresolver spring"; //"fitness";// "ExecutorService";//"EventListener";
        // //"Country"; //"Preconditions";

        // wildcard query
        // String queryString = "te*t";

        // fuzzy query
        // String queryString = "roam~2";

        // phrase query
        // String queryString = "\"apache lucene\"~5";

        // boolean search
        // String queryString = "\"networks\" AND \"protocol\"";

        // boosted search
        // String queryString = "computer^10 crime";

        int hitsPerPage = 100;
        IndexReader reader = DirectoryReader.open(FSDirectory.open(Paths.get(index)));
        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, 1000); //hitsPerPage); //100);

        doSearch(in, searcher, query, hitsPerPage, raw, queries == null && queryString == null);

        reader.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 doSearch(BufferedReader in, IndexSearcher searcher, Query query, int hitsPerPage,
            boolean raw, boolean interactive) throws IOException {
        int page = 1;
        // Collect enough docs to show 5 pages
        TopDocs results = searcher.search(query, page * hitsPerPage);
        ScoreDoc[] hits = results.scoreDocs;

        int numTotalHits = results.totalHits;
        System.out.println(numTotalHits + " total matching documents");

        int offset = hitsPerPage * (page - 1);
        int start = 0;
        int end = Math.min(numTotalHits, offset); //hitsPerPage * page);

        for (int i = start + offset; i < end + offset; i++) {
            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");
            }

        }
    }
}