Class SimpleFacetsExample
Shows simple usage of faceted indexing and search.
Inheritance
System.Object
SimpleFacetsExample
Namespace: Lucene.Net.Demo.Facet
Assembly: Lucene.Net.Demo.dll
Syntax
public class SimpleFacetsExample : objectExamples
using Lucene.Net.Analysis.Core;
using Lucene.Net.Documents;
using Lucene.Net.Facet;
using Lucene.Net.Facet.Taxonomy;
using Lucene.Net.Facet.Taxonomy.Directory;
using Lucene.Net.Index;
using Lucene.Net.Search;
using Lucene.Net.Store;
using Lucene.Net.Util;
using System;
using System.Collections.Generic;
namespace Lucene.Net.Demo.Facet
{
/// <summary>
/// Shows simple usage of faceted indexing and search.
/// </summary>
public class SimpleFacetsExample
{
/// <summary>
/// Using a constant for all functionality related to a specific index
/// is the best strategy. This allows you to upgrade Lucene.Net first
/// and plan the upgrade of the index binary format for a later time.
/// Once the index is upgraded, you simply need to update the constant
/// version and redeploy your application.
/// </summary>
private const LuceneVersion EXAMPLE_VERSION = LuceneVersion.LUCENE_48;
private readonly Directory indexDir = new RAMDirectory();
private readonly Directory taxoDir = new RAMDirectory();
private readonly FacetsConfig config = new FacetsConfig();
/// <summary>Constructor</summary>
public SimpleFacetsExample()
{
config.SetHierarchical("Publish Date", true);
}
/// <summary>Build the example index.</summary>
private void Index()
{
using (IndexWriter indexWriter = new IndexWriter(indexDir, new IndexWriterConfig(EXAMPLE_VERSION,
new WhitespaceAnalyzer(EXAMPLE_VERSION))))
// Writes facet ords to a separate directory from the main index
using (DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(taxoDir))
{
Document doc = new Document();
doc.Add(new FacetField("Author", "Bob"));
doc.Add(new FacetField("Publish Date", "2010", "10", "15"));
indexWriter.AddDocument(config.Build(taxoWriter, doc));
doc = new Document();
doc.Add(new FacetField("Author", "Lisa"));
doc.Add(new FacetField("Publish Date", "2010", "10", "20"));
indexWriter.AddDocument(config.Build(taxoWriter, doc));
doc = new Document();
doc.Add(new FacetField("Author", "Lisa"));
doc.Add(new FacetField("Publish Date", "2012", "1", "1"));
indexWriter.AddDocument(config.Build(taxoWriter, doc));
doc = new Document();
doc.Add(new FacetField("Author", "Susan"));
doc.Add(new FacetField("Publish Date", "2012", "1", "7"));
indexWriter.AddDocument(config.Build(taxoWriter, doc));
doc = new Document();
doc.Add(new FacetField("Author", "Frank"));
doc.Add(new FacetField("Publish Date", "1999", "5", "5"));
indexWriter.AddDocument(config.Build(taxoWriter, doc));
} // Disposes indexWriter and taxoWriter
}
/// <summary>User runs a query and counts facets.</summary>
private IList<FacetResult> FacetsWithSearch()
{
using (DirectoryReader indexReader = DirectoryReader.Open(indexDir))
using (TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir))
{
IndexSearcher searcher = new IndexSearcher(indexReader);
FacetsCollector fc = new FacetsCollector();
// MatchAllDocsQuery is for "browsing" (counts facets
// for all non-deleted docs in the index); normally
// you'd use a "normal" query:
FacetsCollector.Search(searcher, new MatchAllDocsQuery(), 10, fc);
// Retrieve results
IList<FacetResult> results = new List<FacetResult>();
// Count both "Publish Date" and "Author" dimensions
Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
results.Add(facets.GetTopChildren(10, "Author"));
results.Add(facets.GetTopChildren(10, "Publish Date"));
return results;
} // Disposes indexReader and taxoReader
}
/// <summary>User runs a query and counts facets only without collecting the matching documents.</summary>
private IList<FacetResult> FacetsOnly()
{
using (DirectoryReader indexReader = DirectoryReader.Open(indexDir))
using (TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir))
{
IndexSearcher searcher = new IndexSearcher(indexReader);
FacetsCollector fc = new FacetsCollector();
// MatchAllDocsQuery is for "browsing" (counts facets
// for all non-deleted docs in the index); normally
// you'd use a "normal" query:
searcher.Search(new MatchAllDocsQuery(), null /*Filter */, fc);
// Retrieve results
IList<FacetResult> results = new List<FacetResult>();
// Count both "Publish Date" and "Author" dimensions
Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
results.Add(facets.GetTopChildren(10, "Author"));
results.Add(facets.GetTopChildren(10, "Publish Date"));
return results;
} // Disposes indexReader and taxoReader
}
/// <summary>
/// User drills down on 'Publish Date/2010', and we
/// return facets for 'Author'
/// </summary>
private FacetResult DrillDown()
{
using (DirectoryReader indexReader = DirectoryReader.Open(indexDir))
using (TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir))
{
IndexSearcher searcher = new IndexSearcher(indexReader);
// Passing no baseQuery means we drill down on all
// documents ("browse only"):
DrillDownQuery q = new DrillDownQuery(config);
// Now user drills down on Publish Date/2010:
q.Add("Publish Date", "2010");
FacetsCollector fc = new FacetsCollector();
FacetsCollector.Search(searcher, q, 10, fc);
// Retrieve results
Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
FacetResult result = facets.GetTopChildren(10, "Author");
return result;
} // Disposes indexReader and taxoReader
}
/// <summary>
/// User drills down on 'Publish Date/2010', and we
/// return facets for both 'Publish Date' and 'Author',
/// using DrillSideways.
/// </summary>
private IList<FacetResult> DrillSideways()
{
using (DirectoryReader indexReader = DirectoryReader.Open(indexDir))
using (TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir))
{
IndexSearcher searcher = new IndexSearcher(indexReader);
// Passing no baseQuery means we drill down on all
// documents ("browse only"):
DrillDownQuery q = new DrillDownQuery(config);
// Now user drills down on Publish Date/2010:
q.Add("Publish Date", "2010");
DrillSideways ds = new DrillSideways(searcher, config, taxoReader);
DrillSidewaysResult result = ds.Search(q, 10);
// Retrieve results
IList<FacetResult> facets = result.Facets.GetAllDims(10);
return facets;
} // Disposes indexReader and taxoReader
}
/// <summary>Runs the search example.</summary>
public IList<FacetResult> RunFacetOnly()
{
Index();
return FacetsOnly();
}
/// <summary>Runs the search example.</summary>
public IList<FacetResult> RunSearch()
{
Index();
return FacetsWithSearch();
}
/// <summary>Runs the drill-down example.</summary>
public FacetResult RunDrillDown()
{
Index();
return DrillDown();
}
/// <summary>Runs the drill-sideways example.</summary>
public IList<FacetResult> RunDrillSideways()
{
Index();
return DrillSideways();
}
/// <summary>Runs the search and drill-down examples and prints the results.</summary>
public static void Main(string[] args)
{
Console.WriteLine("Facet counting example:");
Console.WriteLine("-----------------------");
SimpleFacetsExample example1 = new SimpleFacetsExample();
IList<FacetResult> results1 = example1.RunFacetOnly();
Console.WriteLine("Author: " + results1[0]);
Console.WriteLine("Publish Date: " + results1[1]);
Console.WriteLine("Facet counting example (combined facets and search):");
Console.WriteLine("-----------------------");
SimpleFacetsExample example = new SimpleFacetsExample();
IList<FacetResult> results = example.RunSearch();
Console.WriteLine("Author: " + results[0]);
Console.WriteLine("Publish Date: " + results[1]);
Console.WriteLine();
Console.WriteLine("Facet drill-down example (Publish Date/2010):");
Console.WriteLine("---------------------------------------------");
Console.WriteLine("Author: " + example.RunDrillDown());
Console.WriteLine();
Console.WriteLine("Facet drill-sideways example (Publish Date/2010):");
Console.WriteLine("---------------------------------------------");
foreach (FacetResult result in example.RunDrillSideways())
{
Console.WriteLine(result);
}
}
}
}
Constructors
| Improve this Doc View SourceSimpleFacetsExample()
Constructor
Declaration
public SimpleFacetsExample()Methods
| Improve this Doc View SourceMain(String[])
Runs the search and drill-down examples and prints the results.
Declaration
public static void Main(string[] args)Parameters
| Type | Name | Description |
|---|---|---|
| System.String[] | args |
RunDrillDown()
Runs the drill-down example.
Declaration
public FacetResult RunDrillDown()Returns
| Type | Description |
|---|---|
| FacetResult |
RunDrillSideways()
Runs the drill-sideways example.
Declaration
public IList<FacetResult> RunDrillSideways()Returns
| Type | Description |
|---|---|
| IList<FacetResult> |
RunFacetOnly()
Runs the search example.
Declaration
public IList<FacetResult> RunFacetOnly()Returns
| Type | Description |
|---|---|
| IList<FacetResult> |
RunSearch()
Runs the search example.
Declaration
public IList<FacetResult> RunSearch()Returns
| Type | Description |
|---|---|
| IList<FacetResult> |