public class Test
{
    private static object syncObj = new object();

    private System.Threading.Timer timer;

    private Searcher searcher;

    private RAMDirectory idx = new RAMDirectory();

    public Test()
    {
        this.timer = new System.Threading.Timer(this.Timer_Elapsed, null, TimeSpan.Zero, TimeSpan.FromMinutes(3));
    }


    private Searcher ESearcher
    {
        get
        {
            return this.searcher;
        }

        set
        {
            lock (syncObj)
            {
                this.searcher = value;
            }
        }
    }

    public Document CreateDocument(string title, string content)
    {
        Document doc = new Document();
        doc.Add(new Field("A", title, Field.Store.YES, Field.Index.NO));
        doc.Add(new Field("B", content, Field.Store.YES, Field.Index.ANALYZED));
        return doc;
    }

    public List<Document> Search(Searcher searcher, string queryString)
    {
        List<Document> documents = new List<Document>();
        QueryParser parser = new QueryParser(Lucene.Net.Util.Version.LUCENE_30, "B", new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30));
        Query query = parser.Parse(queryString);
        int hitsPerPage = 5;
        TopScoreDocCollector collector = TopScoreDocCollector.Create(2 * hitsPerPage, true);
        this.ESearcher.Search(query, collector);

        ScoreDoc[] hits = collector.TopDocs().ScoreDocs;

        int hitCount = collector.TotalHits > 10 ? 10 : collector.TotalHits;
        for (int i = 0; i < hitCount; i++)
        {
            ScoreDoc scoreDoc = hits[i];
            int docId = scoreDoc.Doc;
            float docScore = scoreDoc.Score;
            Document doc = searcher.Doc(docId);
            documents.Add(doc);
        }

        return documents;
    }

    private void Timer_Elapsed(object sender)
    {
        this.Log("Started Updating the Search Indexing");
        // Get New data to Index
        using (IndexWriter writer = new IndexWriter(this.idx, new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30), true, IndexWriter.MaxFieldLength.LIMITED))
        {
            foreach (var e in es)
            {
                writer.AddDocument(this.CreateDocument(e.Value.ToString(), e.Key));
            }

            writer.Optimize();
        }

        this.ESearcher = new IndexSearcher(this.idx);
        this.Log("Completed Updating the Search Indexing");
    }

    public Result ServeRequest()
    {
        var documents = this.Search(this.EntitySearcher, searchTerm);
        //somelogic
        return result;

    }