LuceneSearcher.cs :  » Content-Management-Systems-CMS » Kooboo » Everest » Search » C# / CSharp Open Source

/*
Kooboo is a content management system based on ASP.NET MVC framework. Copyright 2009 Yardi Technology Limited.

This program is free software: you can redistribute it and/or modify it under the terms of the
GNU General Public License version 3 as published by the Free Software Foundation.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program.
If not, see http://www.kooboo.com/gpl3/.
*/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using Lucene.Net.Index;
using Lucene.Net.Search;
using Lucene.Net.Analysis;
using Lucene.Net.Analysis.Standard;

using Everest.Search.Convertor;
using Lucene.Net.Highlight;
namespace Everest.Search{
    /// <summary>
    /// Search use lucene
    /// </summary>
    public class LuceneSearcher : ISearcher
    {
        string directory = string.Empty;
        IDocumentConvertor defaultConvertor;
        /// <summary>
        /// Initializes a new instance of the <see cref="LuceneSearcher"/> class.
        /// </summary>
        public LuceneSearcher()
        {
        }
        /// <summary>
        /// Initializes a new instance of the <see cref="LuceneSearcher"/> class.
        /// </summary>
        /// <param name="directory">The directory.</param>
        /// <param name="documentConvertor">The document convertor.</param>
        public LuceneSearcher(string directory, IDocumentConvertor documentConvertor)
        {
            this.directory = directory;
            defaultConvertor = documentConvertor;
        }
        #region ISearcher Members

        /// <summary>
        /// Searches the specified key.
        /// default search all the field in the class T;
        /// if have configuration ,priority to use the query configuration.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key">The key.</param>
        /// <param name="start">The start.</param>
        /// <param name="limit">The limit.</param>
        /// <param name="totalCount">The total count.</param>
        /// <returns></returns>
        public IEnumerable<T> Search<T>(string key, int start, int limit, out int totalCount) where T : class, new()
        {
            return Search<T>(key, start, limit, out totalCount, null);
        }

        #endregion

        #region ISearcher Members


        /// <summary>
        /// Searches the specified key.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key">The key.</param>
        /// <param name="start">The start.The minimum start index is 1</param>
        /// <param name="limit">The limit.</param>
        /// <param name="totalCount">The total count.</param>
        /// <param name="searchFields">The search fields.</param>
        /// <returns></returns>
        public IEnumerable<T> Search<T>(string key, int start, int limit, out int totalCount, params SearchOption[] searchOptions)
        {
            ConfigurationSerivce configService = new ConfigurationSerivce(typeof(T), directory, defaultConvertor);
            IndexReader reader = null;
            Searcher searcher = null;
            try
            {
                reader = IndexReader.Open(configService.Directory);
                searcher = new IndexSearcher(reader);
                Query query = configService.ParseQuery(key, searchOptions);
                Hits hits = searcher.Search(query);
                totalCount = hits.Length();
                IList<T> list = new List<T>();

                if (start <= totalCount)
                {
                    IDocumentConvertor convertor = configService.GetConvertor();
                    convertor.SetAnalyzer(configService.Analyzer);

                    Lucene.Net.Highlight.Highlighter lighter =
                        new Highlighter(new Lucene.Net.Highlight.QueryScorer(query));
                    convertor.SetHighlighter(lighter);

                    int i = start - 1;
                    if (start < 0)
                    {
                        start = 0;
                    }
                    while (list.Count < limit && i < hits.Length())
                    {
                        T o = (T)convertor.ToObject(hits.Doc(i));

                        list.Add(o);

                        i++;
                    }
                }
                return list;
            }
            finally
            {
                if (searcher != null)
                {
                    searcher.Close();
                }
                if (reader != null)
                {
                    reader.Close();

                }
            }

        }

        #endregion
    }
}