Sample (Eclipse-based) project to play with Lucene. Index, search.

.classpath

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
	<classpathentry kind="src" path="src"/>
	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
	<classpathentry kind="lib" path="lib/lucene-analyzers-common-4.3.1.jar"/>
	<classpathentry kind="lib" path="lib/lucene-core-4.3.1.jar" sourcepath="/lucene-solr"/>
	<classpathentry kind="lib" path="lib/lucene-queryparser-4.3.1.jar"/>
	<classpathentry kind="output" path="bin"/>
</classpath>

.project

<?xml version="1.0" encoding="UTF-8"?>

<projectDescription>
	<name>test-lucene</name>
	<comment></comment>
	<projects>
	</projects>
	<buildSpec>
		<buildCommand>
			<name>org.eclipse.jdt.core.javabuilder</name>
			<arguments>
			</arguments>
		</buildCommand>
	</buildSpec>
	<natures>
		<nature>org.eclipse.jdt.core.javanature</nature>
	</natures>
</projectDescription>

TestLuceneV431.java

/**
 * Copyright (c) 2000-present Liferay, Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 *
 * This library 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 Lesser General Public License for more
 * details.
 */

package com.liferay.test;

import java.io.File;
import java.util.ArrayList;
import java.util.List;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.Fields;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.MultiFields;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.Version;

/**
 * Requires lucene-4.3.1 or later.
 *<p>
 * Dependencies:<br>
 *- lucene-analyzers-common<br>
 *- lucene-core<br>
 *- lucene-queryparser<br>
 *<p>
 * @author Tibor Lipusz
 *<br>
 * Lead Software Engineer, Platform TS, EMEA
 *<br>
 * Search & Security SME, Subscription Services & Release, Global
 *<br>
 * LSV Project Lead
 */
public class TestLuceneV431 {

	public static void main(String[] args) throws Exception {
		try {
			initIndex();

			// -- Index docs --

			Analyzer analyzer = new StandardAnalyzer(_VERSION);

			String fieldName = "test";

			Document document = new Document();

			Field field =
				new TextField(
					fieldName, "null", Field.Store.YES);

			document.add(field);

			addDocument(document, analyzer);

			// Echo terms

			System.out.println(
				"Indexed terms <" + fieldName + ">: " +
				getIndexedTerms(fieldName));

			// Search

			String keyword = "null";

			int searchCount = search(fieldName, keyword, analyzer);

			System.out.println(
				"Number of results searching for: " + keyword + " = " +
				searchCount);
		}
		finally {
			closeIndex(true);
		}
	}

	protected static void addDocument(
			Document document, Analyzer analyzer)
		throws Exception {

		checkIndex();

		_indexWriter.addDocument(document, analyzer);

		_indexWriter.commit();
	}

	protected static void checkIndex() throws Exception {
		if (_indexWriter == null) {
			initIndex();
		}
	}

	protected static void closeIndex(boolean deleteAll) throws Exception {
		if (_indexWriter == null) {
			return;
		}

		if (deleteAll) {
			_indexWriter.deleteAll();
		}

		_indexWriter.close();
	}

	protected static void initIndex() throws Exception {
		_indexDir = FSDirectory.open(new File("index"));

		IndexWriterConfig config =
			new IndexWriterConfig(
				Version.LUCENE_43, new StandardAnalyzer(_VERSION));

		_indexWriter = new IndexWriter(_indexDir, config);
	}

	protected static List<String> getIndexedTerms(
			String lookUpField)
		throws Exception {

		checkIndex();

		IndexReader indexReader = DirectoryReader.open(_indexDir);

		Fields fields = MultiFields.getFields(indexReader);

		List<String> termStrings = new ArrayList<String>();

		for (String field : fields) {
			if (field.equals(lookUpField)) {
				Terms terms = fields.terms(field);

				TermsEnum termsEnum = terms.iterator(null);

				while (true) {
					BytesRef byteRef = termsEnum.next();

					if (byteRef == null) {
						break;
					}

					termStrings.add(byteRef.utf8ToString());
				}
			}
		}

		return termStrings;
	}

	protected static int search(
			String field, String keyword, Analyzer analyzer)
		throws Exception {

		checkIndex();

		IndexReader indexReader = DirectoryReader.open(_indexDir);

		IndexSearcher indexSearcher = new IndexSearcher(indexReader);

		QueryParser queryParser = new QueryParser(_VERSION, field, analyzer);

		Query query = queryParser.parse(keyword);

		// Print query

		System.out.println("Query: " + query);

		TopDocs topDocs = indexSearcher.search(query, 100);

		return topDocs.totalHits;
	}

	private static Directory _indexDir;
	private static IndexWriter _indexWriter;

	private static final Version _VERSION = Version.LUCENE_43;

}