1 全文检索工具，方便实现全文检索功能。
2 全文检索， 先对要搜索的文档进行分词，形成索引，根据索引经行检索。
3 全文检索流程
索引流程：采集数据， 处理数据，创建索引
搜索流程：输入查询条件，Lucene查询器查询索引， 索引库取出结果
4 IndexWriter是索引过程的核心组件，通过IndexWriter可以创建新索引、更新索引、删除索引操作。IndexWriter需要通过Directory对索引进行存储操作。
Directory描述了索引的存储位置，底层封装了I/O操作，负责对索引进行存储。它是一个抽象类，它的子类常用的包括FSDirectory（在文件系统存储索引）、RAMDirectory（在内存存储索引）。
public class IndexManager { ???@Test ???public void createIndex() throws Exception { ???????BookDao bookDao = new BookDaoImpl(); ???????List<Book> books = bookDao.queryBooks(); ???????List<Document> documents = new ArrayList<>(); ???????????????Document document = null; ???????for (Book book : books) { ???????????document = new Document(); ???????????Field id = new TextField("id", book.getId().toString(), Store.YES); ???????????Field name = new TextField("name", book.getName(), Store.YES); ???????????Field price = new TextField("price", book.getPrice().toString(), Store.YES); ???????????Field detail = new TextField("detail", book.getDetail(), Store.YES); ???????????document.add(id); ???????????document.add(name); ???????????document.add(price); ???????????document.add(detail); ???????????documents.add(document); ???????} ???????????????Analyzer analyzer = new StandardAnalyzer(); ???????IndexWriter indexWriter = null; ???????IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_4_10_3, analyzer); ???????Directory directory = FSDirectory.open(new File("E:\\index\\")); ???????indexWriter = new IndexWriter(directory, config); ???????????????for (Document d : documents) { ???????????indexWriter.addDocument(d); ???????} ???????indexWriter.close(); ???}}5 搜索输入语法 and or not 大写
???public void indexSearch() throws Exception { ???????QueryParser queryParser = new QueryParser("detail", new StandardAnalyzer()); ???????Query query = queryParser.parse("detail:好 AND 大"); ???????Directory directory = FSDirectory.open(new File("E:\\index\\")); ???????IndexReader indexReader = DirectoryReader.open(directory); ???????IndexSearcher searcher = new IndexSearcher(indexReader); ???????TopDocs docs = searcher.search(query, 10); ???????ScoreDoc[] scoreDocs = docs.scoreDocs; ???????for (ScoreDoc scoreDoc : scoreDocs) { ???????????int docId = scoreDoc.doc; ???????????Document document = searcher.doc(docId); ???????????System.out.println(document.get("id")); ???????????System.out.println(document.get("name")); ???????????System.out.println(document.get("detail")); ???????} ???????indexReader.close(); ???}5 field 属性
1 是否分词 tokenized 分词为了索引，（商品名称，描述，价格），不分词也可以索引（商品id）
2 是否索引ndexed
3 是否存储 stored 是否将field存到文档域中，存储目的显示。 名称，价格，id，图片地址
@Test ???public void createIndex() throws Exception { ???????BookDao bookDao = new BookDaoImpl(); ???????List<Book> books = bookDao.queryBooks(); ???????List<Document> documents = new ArrayList<>(); ???????????????Document document = null; ???????for (Book book : books) { ???????????document = new Document(); ???????????Field id = new StringField("id", book.getId().toString(), Store.YES); ???????????Field name = new TextField("name", book.getName(), Store.YES); ???????????Field price = new FloatField("price", book.getPrice(), Store.YES); ???????????Field detail = new TextField("detail", book.getDetail(), Store.NO); ???????????document.add(id); ???????????document.add(name); ???????????document.add(price); ???????????document.add(detail); ???????????documents.add(document); ???????} ???????????????Analyzer analyzer = new StandardAnalyzer(); ???????IndexWriter indexWriter = null; ???????IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_4_10_3, analyzer); ???????Directory directory = FSDirectory.open(new File("E:\\index\\")); ???????indexWriter = new IndexWriter(directory, config); ???????????????for (Document d : documents) { ???????????indexWriter.addDocument(d); ???????} ???????indexWriter.close(); ???}}6 修改索引
???@Test ???public void updateIndex() throws Exception { ???????Analyzer analyzer = new StandardAnalyzer(); ???????IndexWriter indexWriter = null; ???????IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_4_10_3, analyzer); ???????Directory directory = FSDirectory.open(new File("E:\\index\\")); ???????indexWriter = new IndexWriter(directory, config); ???????Document document = new Document(); ???????document.add(new TextField("name", "fdrr", Store.YES)); ???????indexWriter.updateDocument(new Term("name", "fddd"), document); ???????indexWriter.close(); ???}lucene
原文地址：http://www.cnblogs.com/whesuanfa/p/7624730.html