lucene 近实时搜索实例

package com.jiepu.lucene_30;

import org.apache.lucene.util.Version;
import org.apache.lucene.store.*;
import org.apache.lucene.index.*;
import org.apache.lucene.search.*;
import org.apache.lucene.document.*;
import org.apache.lucene.analysis.standard.StandardAnalyzer;

import junit.framework.TestCase;

//lucene 近实时搜索的实现
// From chapter 3
public class NearRealTimeTest extends TestCase {

	public void testNearRealTime() throws Exception {
		Directory dir = new RAMDirectory();
		IndexWriter writer = new IndexWriter(dir, new StandardAnalyzer(
				Version.LUCENE_30), IndexWriter.MaxFieldLength.UNLIMITED);
		for (int i = 0; i < 10; i++) {
			Document doc = new Document();
			doc.add(new Field("id", "" + i, Field.Store.NO,
					Field.Index.NOT_ANALYZED_NO_NORMS));
			doc.add(new Field("text", "aaa", Field.Store.NO,
					Field.Index.ANALYZED));
			writer.addDocument(doc);
		}
		IndexReader reader = writer.getReader(); // #1
		IndexSearcher searcher = new IndexSearcher(reader); // #A

		Query query = new TermQuery(new Term("text", "aaa"));
		TopDocs docs = searcher.search(query, 1);
		assertEquals(10, docs.totalHits); // #B

		writer.deleteDocuments(new Term("id", "7")); // #2

		Document doc = new Document(); // #3
		doc.add(new Field("id", // #3
				"11", // #3
				Field.Store.NO, // #3
				Field.Index.NOT_ANALYZED_NO_NORMS)); // #3
		doc.add(new Field("text", // #3
				"bbb", // #3
				Field.Store.NO, // #3
				Field.Index.ANALYZED)); // #3
		writer.addDocument(doc); // #3

		IndexReader newReader = reader.reopen(); // #4
		assertFalse(reader == newReader); // #5
		reader.close(); // #6
		searcher = new IndexSearcher(newReader);

		TopDocs hits = searcher.search(query, 10); // #7
		assertEquals(9, hits.totalHits); // #7

		query = new TermQuery(new Term("text", "bbb")); // #8
		hits = searcher.search(query, 1); // #8
		assertEquals(1, hits.totalHits); // #8

		newReader.close();
		writer.close();
	}
}

/*
 * #1 Create near-real-time reader #A Wrap reader in IndexSearcher #B Search
 * returns 10 hits #2 Delete 1 document #3 Add 1 document #4 Reopen reader #5
 * Confirm reader is new #6 Close old reader #7 Verify 9 hits now #8 Confirm new
 * document matched
 */