src/Lucene.Net.Tests.Classification/ClassificationTestBase.cs - lucenenet - Git at Google

 using System;
 using System.Diagnostics;
 using System.Text;
 using Lucene.Net.Analysis;
 using Lucene.Net.Documents;
 using Lucene.Net.Index;
 using Lucene.Net.Search;
 using Lucene.Net.Store;
 using Lucene.Net.Util;
 using NUnit.Framework;
 using Assert = Lucene.Net.TestFramework.Assert;

 namespace Lucene.Net.Classification
 {
     /*
      * 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.
      */

     /**
      * Base class for testing <see cref="IClassifier{T}"/>s
      */
     public abstract class ClassificationTestBase<T> : Util.LuceneTestCase
     {
         public readonly static String POLITICS_INPUT = "Here are some interesting questions and answers about Mitt Romney.. " +
             "If you don't know the answer to the question about Mitt Romney, then simply click on the answer below the question section.";
         public static readonly BytesRef POLITICS_RESULT = new BytesRef("politics");

         public static readonly String TECHNOLOGY_INPUT = "Much is made of what the likes of Facebook, Google and Apple know about users." +
             " Truth is, Amazon may know more.";
         public static readonly BytesRef TECHNOLOGY_RESULT = new BytesRef("technology");

         private RandomIndexWriter indexWriter;
         private Directory dir;
         private FieldType ft;

         protected String textFieldName;
         protected String categoryFieldName;

         String booleanFieldName;

         [SetUp]
         public override void SetUp()
         {
             base.SetUp();
             dir = NewDirectory();
             indexWriter = new RandomIndexWriter(
 #if FEATURE_INSTANCE_TESTDATA_INITIALIZATION
                 this,
 #endif
                 Random, dir);
             textFieldName = "text";
             categoryFieldName = "cat";
             booleanFieldName = "bool";
             ft = new FieldType(TextField.TYPE_STORED);
             ft.StoreTermVectors = true;
             ft.StoreTermVectorOffsets = true;
             ft.StoreTermVectorPositions = true;
         }

         [TearDown]
         public override void TearDown()
         {
             indexWriter.Dispose();
             dir.Dispose();
             base.TearDown();
         }

         protected void CheckCorrectClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName)
         {
             CheckCorrectClassification(classifier, inputDoc, expectedResult, analyzer, textFieldName, classFieldName, null);
         }

         protected void CheckCorrectClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName, Query query)
         {
             AtomicReader atomicReader = null;
             try
             {
                 PopulateSampleIndex(analyzer);
                 atomicReader = SlowCompositeReaderWrapper.Wrap(indexWriter.GetReader());
                 classifier.Train(atomicReader, textFieldName, classFieldName, analyzer, query);
                 ClassificationResult<T> classificationResult = classifier.AssignClass(inputDoc);
                 Assert.NotNull(classificationResult.AssignedClass);
                 Assert.AreEqual(expectedResult, classificationResult.AssignedClass, "got an assigned class of " + classificationResult.AssignedClass);
                 Assert.IsTrue(classificationResult.Score > 0, "got a not positive score " + classificationResult.Score);
             }
             finally
             {
                 if (atomicReader != null)
                     atomicReader.Dispose();
             }
         }
         protected void CheckOnlineClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName)
         {
             CheckOnlineClassification(classifier, inputDoc, expectedResult, analyzer, textFieldName, classFieldName, null);
         }

         protected void CheckOnlineClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName, Query query)
         {
             AtomicReader atomicReader = null;
             try
             {
                 PopulateSampleIndex(analyzer);
                 atomicReader = SlowCompositeReaderWrapper.Wrap(indexWriter.GetReader());
                 classifier.Train(atomicReader, textFieldName, classFieldName, analyzer, query);
                 ClassificationResult<T> classificationResult = classifier.AssignClass(inputDoc);
                 Assert.NotNull(classificationResult.AssignedClass);
                 Assert.AreEqual(expectedResult, classificationResult.AssignedClass, "got an assigned class of " + classificationResult.AssignedClass);
                 Assert.IsTrue(classificationResult.Score > 0, "got a not positive score " + classificationResult.Score);
                 UpdateSampleIndex(analyzer);
                 ClassificationResult<T> secondClassificationResult = classifier.AssignClass(inputDoc);
                 Equals(classificationResult.AssignedClass, secondClassificationResult.AssignedClass);
                 Equals(classificationResult.Score, secondClassificationResult.Score);

             }
             finally
             {
                 if (atomicReader != null)
                     atomicReader.Dispose();
             }
         }

         private void PopulateSampleIndex(Analyzer analyzer)
         {
             indexWriter.DeleteAll();
             indexWriter.Commit();

             String text;

             Document doc = new Document();
             text = "The traveling press secretary for Mitt Romney lost his cool and cursed at reporters " +
                 "who attempted to ask questions of the Republican presidential candidate in a public plaza near the Tomb of " +
                 "the Unknown Soldier in Warsaw Tuesday.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));

             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Mitt Romney seeks to assure Israel and Iran, as well as Jewish voters in the United" +
                 " States, that he will be tougher against Iran's nuclear ambitions than President Barack Obama.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "And there's a threshold question that he has to answer for the American people and " +
                 "that's whether he is prepared to be commander-in-chief,\" she continued. \"As we look to the past events, we " +
                 "know that this raises some questions about his preparedness and we'll see how the rest of his trip goes.\"";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Still, when it comes to gun policy, many congressional Democrats have \"decided to " +
                 "keep quiet and not go there,\" said Alan Lizotte, dean and professor at the State University of New York at " +
                 "Albany's School of Criminal Justice.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Standing amongst the thousands of people at the state Capitol, Jorstad, director of " +
                 "technology at the University of Wisconsin-La Crosse, documented the historic moment and shared it with the " +
                 "world through the Internet.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "technology", ft));
             doc.Add(new Field(booleanFieldName, "false", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "So, about all those experts and analysts who've spent the past year or so saying " +
                 "Facebook was going to make a phone. A new expert has stepped forward to say it's not going to happen.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "technology", ft));
             doc.Add(new Field(booleanFieldName, "false", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "More than 400 million people trust Google with their e-mail, and 50 million store files" +
                 " in the cloud using the Dropbox service. People manage their bank accounts, pay bills, trade stocks and " +
                 "generally transfer or store huge volumes of personal data online.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "technology", ft));
             doc.Add(new Field(booleanFieldName, "false", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "unlabeled doc";
             doc.Add(new Field(textFieldName, text, ft));
             indexWriter.AddDocument(doc, analyzer);

             indexWriter.Commit();
         }

         protected void CheckPerformance(IClassifier<T> classifier, Analyzer analyzer, String classFieldName)
         {
             AtomicReader atomicReader = null;
             var stopwatch = new Stopwatch();
             stopwatch.Start();
             try
             {
                 PopulatePerformanceIndex(analyzer);
                 atomicReader = SlowCompositeReaderWrapper.Wrap(indexWriter.GetReader());
                 classifier.Train(atomicReader, textFieldName, classFieldName, analyzer);
                 stopwatch.Stop();
                 long trainTime = stopwatch.ElapsedMilliseconds;
                 Assert.IsTrue(trainTime < 120000, "training took more than 2 mins : " + trainTime / 1000 + "s");
             }
             finally
             {
                 if (atomicReader != null)
                     atomicReader.Dispose();
             }
         }

         private void PopulatePerformanceIndex(Analyzer analyzer)
         {
             indexWriter.DeleteAll();
             indexWriter.Commit();

             FieldType ft = new FieldType(TextField.TYPE_STORED);
             ft.StoreTermVectors = true;
             ft.StoreTermVectorOffsets = true;
             ft.StoreTermVectorPositions = true;
             int docs = 1000;
             Random random = new Random();
             for (int i = 0; i < docs; i++)
             {
                 Boolean b = random.NextBoolean();
                 Document doc = new Document();
                 doc.Add(new Field(textFieldName, createRandomString(random), ft));
                 doc.Add(new Field(categoryFieldName, b ? "technology" : "politics", ft));
                 doc.Add(new Field(booleanFieldName, b.ToString(), ft));
                 indexWriter.AddDocument(doc, analyzer);
             }
             indexWriter.Commit();
         }

         private String createRandomString(Random random)
         {
             StringBuilder builder = new StringBuilder();
             for (int i = 0; i < 20; i++)
             {
                 builder.Append(TestUtil.RandomSimpleString(random, 5));
                 builder.Append(" ");
             }
             return builder.ToString();
         }

         private void UpdateSampleIndex(Analyzer analyzer)
         {
             String text;

             Document doc = new Document();
             text = "Warren Bennis says John F. Kennedy grasped a key lesson about the presidency that few have followed.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));

             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Julian Zelizer says Bill Clinton is still trying to shape his party, years after the White House, while George W. Bush opts for a much more passive role.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Crossfire: Sen. Tim Scott passes on Sen. Lindsey Graham endorsement";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Illinois becomes 16th state to allow same-sex marriage.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "politics", ft));
             doc.Add(new Field(booleanFieldName, "true", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Apple is developing iPhones with curved-glass screens and enhanced sensors that detect different levels of pressure, according to a new report.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "technology", ft));
             doc.Add(new Field(booleanFieldName, "false", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "The Xbox One is Microsoft's first new gaming console in eight years. It's a quality piece of hardware but it's also noteworthy because Microsoft is using it to make a statement.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "technology", ft));
             doc.Add(new Field(booleanFieldName, "false", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "Google says it will replace a Google Maps image after a California father complained it shows the body of his teen-age son, who was shot to death in 2009.";
             doc.Add(new Field(textFieldName, text, ft));
             doc.Add(new Field(categoryFieldName, "technology", ft));
             doc.Add(new Field(booleanFieldName, "false", ft));
             indexWriter.AddDocument(doc, analyzer);

             doc = new Document();
             text = "second unlabeled doc";
             doc.Add(new Field(textFieldName, text, ft));
             indexWriter.AddDocument(doc, analyzer);

             indexWriter.Commit();
         }
     }
 }
	using System;
	using System.Diagnostics;
	using System.Text;
	using Lucene.Net.Analysis;
	using Lucene.Net.Documents;
	using Lucene.Net.Index;
	using Lucene.Net.Search;
	using Lucene.Net.Store;
	using Lucene.Net.Util;
	using NUnit.Framework;
	using Assert = Lucene.Net.TestFramework.Assert;

	namespace Lucene.Net.Classification
	{
	/*
	* 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.
	*/

	/**
	* Base class for testing <see cref="IClassifier{T}"/>s
	*/
	public abstract class ClassificationTestBase<T> : Util.LuceneTestCase
	{
	public readonly static String POLITICS_INPUT = "Here are some interesting questions and answers about Mitt Romney.. " +
	"If you don't know the answer to the question about Mitt Romney, then simply click on the answer below the question section.";
	public static readonly BytesRef POLITICS_RESULT = new BytesRef("politics");

	public static readonly String TECHNOLOGY_INPUT = "Much is made of what the likes of Facebook, Google and Apple know about users." +
	" Truth is, Amazon may know more.";
	public static readonly BytesRef TECHNOLOGY_RESULT = new BytesRef("technology");

	private RandomIndexWriter indexWriter;
	private Directory dir;
	private FieldType ft;

	protected String textFieldName;
	protected String categoryFieldName;

	String booleanFieldName;

	[SetUp]
	public override void SetUp()
	{
	base.SetUp();
	dir = NewDirectory();
	indexWriter = new RandomIndexWriter(
	#if FEATURE_INSTANCE_TESTDATA_INITIALIZATION
	this,
	#endif
	Random, dir);
	textFieldName = "text";
	categoryFieldName = "cat";
	booleanFieldName = "bool";
	ft = new FieldType(TextField.TYPE_STORED);
	ft.StoreTermVectors = true;
	ft.StoreTermVectorOffsets = true;
	ft.StoreTermVectorPositions = true;
	}

	[TearDown]
	public override void TearDown()
	{
	indexWriter.Dispose();
	dir.Dispose();
	base.TearDown();
	}

	protected void CheckCorrectClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName)
	{
	CheckCorrectClassification(classifier, inputDoc, expectedResult, analyzer, textFieldName, classFieldName, null);
	}

	protected void CheckCorrectClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName, Query query)
	{
	AtomicReader atomicReader = null;
	try
	{
	PopulateSampleIndex(analyzer);
	atomicReader = SlowCompositeReaderWrapper.Wrap(indexWriter.GetReader());
	classifier.Train(atomicReader, textFieldName, classFieldName, analyzer, query);
	ClassificationResult<T> classificationResult = classifier.AssignClass(inputDoc);
	Assert.NotNull(classificationResult.AssignedClass);
	Assert.AreEqual(expectedResult, classificationResult.AssignedClass, "got an assigned class of " + classificationResult.AssignedClass);
	Assert.IsTrue(classificationResult.Score > 0, "got a not positive score " + classificationResult.Score);
	}
	finally
	{
	if (atomicReader != null)
	atomicReader.Dispose();
	}
	}
	protected void CheckOnlineClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName)
	{
	CheckOnlineClassification(classifier, inputDoc, expectedResult, analyzer, textFieldName, classFieldName, null);
	}

	protected void CheckOnlineClassification(IClassifier<T> classifier, String inputDoc, T expectedResult, Analyzer analyzer, String textFieldName, String classFieldName, Query query)
	{
	AtomicReader atomicReader = null;
	try
	{
	PopulateSampleIndex(analyzer);
	atomicReader = SlowCompositeReaderWrapper.Wrap(indexWriter.GetReader());
	classifier.Train(atomicReader, textFieldName, classFieldName, analyzer, query);
	ClassificationResult<T> classificationResult = classifier.AssignClass(inputDoc);
	Assert.NotNull(classificationResult.AssignedClass);
	Assert.AreEqual(expectedResult, classificationResult.AssignedClass, "got an assigned class of " + classificationResult.AssignedClass);
	Assert.IsTrue(classificationResult.Score > 0, "got a not positive score " + classificationResult.Score);
	UpdateSampleIndex(analyzer);
	ClassificationResult<T> secondClassificationResult = classifier.AssignClass(inputDoc);
	Equals(classificationResult.AssignedClass, secondClassificationResult.AssignedClass);
	Equals(classificationResult.Score, secondClassificationResult.Score);

	}
	finally
	{
	if (atomicReader != null)
	atomicReader.Dispose();
	}
	}

	private void PopulateSampleIndex(Analyzer analyzer)
	{
	indexWriter.DeleteAll();
	indexWriter.Commit();

	String text;

	Document doc = new Document();
	text = "The traveling press secretary for Mitt Romney lost his cool and cursed at reporters " +
	"who attempted to ask questions of the Republican presidential candidate in a public plaza near the Tomb of " +
	"the Unknown Soldier in Warsaw Tuesday.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));

	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Mitt Romney seeks to assure Israel and Iran, as well as Jewish voters in the United" +
	" States, that he will be tougher against Iran's nuclear ambitions than President Barack Obama.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "And there's a threshold question that he has to answer for the American people and " +
	"that's whether he is prepared to be commander-in-chief,\" she continued. \"As we look to the past events, we " +
	"know that this raises some questions about his preparedness and we'll see how the rest of his trip goes.\"";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Still, when it comes to gun policy, many congressional Democrats have \"decided to " +
	"keep quiet and not go there,\" said Alan Lizotte, dean and professor at the State University of New York at " +
	"Albany's School of Criminal Justice.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Standing amongst the thousands of people at the state Capitol, Jorstad, director of " +
	"technology at the University of Wisconsin-La Crosse, documented the historic moment and shared it with the " +
	"world through the Internet.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "technology", ft));
	doc.Add(new Field(booleanFieldName, "false", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "So, about all those experts and analysts who've spent the past year or so saying " +
	"Facebook was going to make a phone. A new expert has stepped forward to say it's not going to happen.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "technology", ft));
	doc.Add(new Field(booleanFieldName, "false", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "More than 400 million people trust Google with their e-mail, and 50 million store files" +
	" in the cloud using the Dropbox service. People manage their bank accounts, pay bills, trade stocks and " +
	"generally transfer or store huge volumes of personal data online.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "technology", ft));
	doc.Add(new Field(booleanFieldName, "false", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "unlabeled doc";
	doc.Add(new Field(textFieldName, text, ft));
	indexWriter.AddDocument(doc, analyzer);

	indexWriter.Commit();
	}

	protected void CheckPerformance(IClassifier<T> classifier, Analyzer analyzer, String classFieldName)
	{
	AtomicReader atomicReader = null;
	var stopwatch = new Stopwatch();
	stopwatch.Start();
	try
	{
	PopulatePerformanceIndex(analyzer);
	atomicReader = SlowCompositeReaderWrapper.Wrap(indexWriter.GetReader());
	classifier.Train(atomicReader, textFieldName, classFieldName, analyzer);
	stopwatch.Stop();
	long trainTime = stopwatch.ElapsedMilliseconds;
	Assert.IsTrue(trainTime < 120000, "training took more than 2 mins : " + trainTime / 1000 + "s");
	}
	finally
	{
	if (atomicReader != null)
	atomicReader.Dispose();
	}
	}

	private void PopulatePerformanceIndex(Analyzer analyzer)
	{
	indexWriter.DeleteAll();
	indexWriter.Commit();

	FieldType ft = new FieldType(TextField.TYPE_STORED);
	ft.StoreTermVectors = true;
	ft.StoreTermVectorOffsets = true;
	ft.StoreTermVectorPositions = true;
	int docs = 1000;
	Random random = new Random();
	for (int i = 0; i < docs; i++)
	{
	Boolean b = random.NextBoolean();
	Document doc = new Document();
	doc.Add(new Field(textFieldName, createRandomString(random), ft));
	doc.Add(new Field(categoryFieldName, b ? "technology" : "politics", ft));
	doc.Add(new Field(booleanFieldName, b.ToString(), ft));
	indexWriter.AddDocument(doc, analyzer);
	}
	indexWriter.Commit();
	}

	private String createRandomString(Random random)
	{
	StringBuilder builder = new StringBuilder();
	for (int i = 0; i < 20; i++)
	{
	builder.Append(TestUtil.RandomSimpleString(random, 5));
	builder.Append(" ");
	}
	return builder.ToString();
	}

	private void UpdateSampleIndex(Analyzer analyzer)
	{
	String text;

	Document doc = new Document();
	text = "Warren Bennis says John F. Kennedy grasped a key lesson about the presidency that few have followed.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));

	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Julian Zelizer says Bill Clinton is still trying to shape his party, years after the White House, while George W. Bush opts for a much more passive role.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Crossfire: Sen. Tim Scott passes on Sen. Lindsey Graham endorsement";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Illinois becomes 16th state to allow same-sex marriage.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "politics", ft));
	doc.Add(new Field(booleanFieldName, "true", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Apple is developing iPhones with curved-glass screens and enhanced sensors that detect different levels of pressure, according to a new report.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "technology", ft));
	doc.Add(new Field(booleanFieldName, "false", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "The Xbox One is Microsoft's first new gaming console in eight years. It's a quality piece of hardware but it's also noteworthy because Microsoft is using it to make a statement.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "technology", ft));
	doc.Add(new Field(booleanFieldName, "false", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "Google says it will replace a Google Maps image after a California father complained it shows the body of his teen-age son, who was shot to death in 2009.";
	doc.Add(new Field(textFieldName, text, ft));
	doc.Add(new Field(categoryFieldName, "technology", ft));
	doc.Add(new Field(booleanFieldName, "false", ft));
	indexWriter.AddDocument(doc, analyzer);

	doc = new Document();
	text = "second unlabeled doc";
	doc.Add(new Field(textFieldName, text, ft));
	indexWriter.AddDocument(doc, analyzer);

	indexWriter.Commit();
	}
	}
	}