public static void AutoCompleteSample()
{
Directory dir = new RAMDirectory();
// Create n-edge grams for field suggestionText
Analyzer analyzer = new EdgeNGramAnalyzer(Version);
var indexWriter = new IndexWriter(dir, analyzer, IndexWriter.MaxFieldLength.UNLIMITED);
var docs = CreateAutoCompleteDocuments(GetDeals());
foreach (var doc in docs)
{
indexWriter.AddDocument(doc);
}
indexWriter.Commit();
indexWriter.Dispose();
var searcherManager = new SearcherManager(dir);
// Default sort by dicount pct desc.
var sort = new Sort(new SortField(DiscountPctFieldName, SortField.INT, true));
const int maxSuggestions = 5;
for (;;)
{
Console.Write("Enter a text for auto completion and press enter: ");
var input = Console.ReadLine();
Query query = new TermQuery(new Term(SuggestionTextFieldName, input));
var searcher = searcherManager.GetSearcher();
TopDocs hits;
try
{
hits = searcher.Search(query, null, maxSuggestions, sort);
}
finally
{
searcherManager.ReleaseSearcher(searcher);
}
foreach (ScoreDoc match in hits.ScoreDocs)
{
Document doc = searcher.Doc(match.Doc);
Console.WriteLine("Matched: '{0}' in '{1}' by '{2}'",
doc.Get(SuggestionTextFieldName), doc.Get(LocationNameFieldName), doc.Get(SupplierFieldName));
}
}
}
/// <summary>
/// Create edge n-grams for each term. Store the terms (n-grams) and the term frequency in the directory.
/// </summary>
/// <param name="directory"></param>
/// <param name="termsMap"></param>
private static void BuildAutoSuggestIndex(Directory directory, Dictionary <string, int> termsMap)
{
var analyzer = new EdgeNGramAnalyzer(Lucene.Net.Util.Version.LUCENE_29);
var writer = new IndexWriter(directory, analyzer, true, IndexWriter.MaxFieldLength.LIMITED);
writer.SetRAMBufferSizeMB(64d);
writer.MergeFactor = 300;
foreach (var term in termsMap.Keys)
{
var doc = new Document();
doc.Add(new Field(NGramTermField, term, Field.Store.YES, Field.Index.ANALYZED_NO_NORMS));
doc.Add(new Field(TermFreqField, termsMap[term].ToString(), Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS));
writer.AddDocument(doc);
}
writer.Optimize();
writer.Commit();
writer.Dispose();
}
