Lucene学习入门2
一、lucene简单的增删改查，如果是新项目，在做完对数据库的DAO操作时，紧跟着做对索引库的增删改查，在维护以前的项目时，再不允许修改源代码的情况下，只能做定时创建索引
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package com.lucene.luceneutil;import org.apache.lucene.document.Document;import org.apache.lucene.document.Field;import org.apache.lucene.document.Field.Index;import org.apache.lucene.document.Field.Store;import com.lucene.entity.ArticleEntity;public class ArticleDocumentUtils {/*** 把ArticleEntity转换成Document对象* @param article ArticleEntity对象* @return 转换后的doc对象*/public static Document Article2Document(ArticleEntity article){String strId = article.getId().toString();Document doc = new Document();doc.add(new Field("id",strId,Store.YES,Index.NOT_ANALYZED));doc.add(new Field("title",article.getTitle(),Store.YES,Index.ANALYZED));doc.add(new Field("content",article.getContent(),Store.YES,Index.ANALYZED));return doc ;}public static ArticleEntity Document2Article(Document doc){ArticleEntity article = new ArticleEntity();Integer id = Integer.parseInt(doc.get("id")) ;article.setId(id);article.setTitle(doc.get("title"));article.setContent(doc.get("content"));return article ;}}package com.lucene.luceneutil;import java.io.File;import org.apache.lucene.analysis.Analyzer;import org.apache.lucene.analysis.standard.StandardAnalyzer;import org.apache.lucene.store.Directory;import org.apache.lucene.store.FSDirectory;import org.apache.lucene.util.Version;public class Configuration {private static Directory directory ;private static Analyzer analyzer ;static {try {directory = FSDirectory.open(new File("./filepath"));analyzer = new StandardAnalyzer(Version.LUCENE_30 );} catch (Exception e) {new RuntimeException(e);}}public static Directory getDirectory() {return directory;}public static Analyzer getAnalyzer() {return analyzer;}}package com.lucene.entity;import java.util.List;public class QueryResult<T> {private int count ;private List<T> list ;public QueryResult(int count, List<T> list) {this.count = count;this.list = list;}public int getCount() {return count;}public void setCount(int count) {this.count = count;}public List<T> getList() {return list;}public void setList(List<T> list) {this.list = list;}}package com.lucene.indexdao;import com.lucene.entity.ArticleEntity;import com.lucene.entity.QueryResult;public interface ArticleEntityIndexDao {/*** 建立索引（保存到索引库）* * @param article*/public void save(ArticleEntity article);/*** 删除索引* @param id*/public void delete(Integer id);/*** 更新文章* @param article 要更新的文章*/public void update(ArticleEntity article) ;/*** * @param query 查询条件* @param firstResult 每页开始的条数* @param number 每页显示的条数* @return 返回符合条件的结果*/public QueryResult<ArticleEntity> search(String query,int firstResult ,int number);}package com.lucene.indexdao.impl;import java.util.ArrayList;import java.util.List;import org.apache.lucene.document.Document;import org.apache.lucene.index.IndexWriter;import org.apache.lucene.index.IndexWriter.MaxFieldLength;import org.apache.lucene.index.Term;import org.apache.lucene.queryParser.MultiFieldQueryParser;import org.apache.lucene.queryParser.QueryParser;import org.apache.lucene.search.IndexSearcher;import org.apache.lucene.search.Query;import org.apache.lucene.search.ScoreDoc;import org.apache.lucene.search.TopDocs;import org.apache.lucene.util.Version;import com.lucene.entity.ArticleEntity;import com.lucene.entity.QueryResult;import com.lucene.indexdao.ArticleEntityIndexDao;import com.lucene.luceneutil.ArticleDocumentUtils;import com.lucene.luceneutil.Configuration;public class ArticleEntityIndexDaoImpl implements ArticleEntityIndexDao {@Overridepublic void save(ArticleEntity article) {// 1，把Article转为DocumentDocument doc = ArticleDocumentUtils.Article2Document(article);// 2，把Document存到索引库中IndexWriter indexWrite = null ;try {indexWrite = new IndexWriter(Configuration.getDirectory(), Configuration.getAnalyzer(), MaxFieldLength.LIMITED);indexWrite.addDocument(doc);// 建立索引} catch (Exception e) {throw new RuntimeException(e);}finally{try {indexWrite.close();} catch (Exception e) {throw new RuntimeException();} }}/*** Term：就是某Field中的某个关键词。*/@Overridepublic void delete(Integer id) {IndexWriter indexWrite = null ;try {Term term = new Term("id",id.toString());indexWrite = new IndexWriter(Configuration.getDirectory(), Configuration.getAnalyzer(), MaxFieldLength.LIMITED);indexWrite.deleteDocuments(term);} catch (Exception e) {throw new RuntimeException(e);}finally{try {indexWrite.close();} catch (Exception e) {throw new RuntimeException();} }}/*** 更新就是先删除再添加*/@Overridepublic void update(ArticleEntity article) {IndexWriter indexWrite = null ;try {Term term = new Term("id",article.toString());Document doc = ArticleDocumentUtils.Article2Document(article);indexWrite = new IndexWriter(Configuration.getDirectory(), Configuration.getAnalyzer(), MaxFieldLength.LIMITED);indexWrite.updateDocument(term, doc);//indexWrite.deleteDocuments(term);//indexWrite.addDocument(doc);} catch (Exception e) {throw new RuntimeException(e);}finally{try {indexWrite.close();} catch (Exception e) {throw new RuntimeException();} }}@Overridepublic QueryResult<ArticleEntity> search(String query, int firstResult,int number) { IndexSearcher searchQuery = null ; QueryParser queryParser = null; Query queryStr; try { //queryParser = new QueryParser(Version.LUCENE_30, "title", Configuration.getAnalyzer());这是默认在title里搜索 queryParser = new MultiFieldQueryParser(Version.LUCENE_30,new String[]{"title","content"}, Configuration.getAnalyzer());//多字段中搜索 queryStr = queryParser.parse(query); searchQuery = new IndexSearcher(Configuration.getDirectory()); TopDocs topDocs = searchQuery.search(queryStr, 1000); int totalNum = topDocs.totalHits ;//符合条件的总记录数 ScoreDoc[] scoredoc = topDocs.scoreDocs ;//符合条件的前n条信息 //处理结果 List<ArticleEntity> list = new ArrayList(); int endLenght = Math.max(firstResult+number, scoredoc.length); for(int i = firstResult ; i < endLenght ; i++){ Document doc = searchQuery.doc(scoredoc[i].doc) ; //得到Document对象 ArticleEntity e =ArticleDocumentUtils.Document2Article(doc); //得到ArticleEntity对象 list.add(e); } return new QueryResult(totalNum,list); } catch (Exception e) { throw new RuntimeException(e); }finally{ try { searchQuery.close(); } catch (Exception e) { throw new RuntimeException(e); } } }}?二、对简单的增删改查做完了，单个的测试是没有问题，但是同时有多个IndexWriter在运行的时候就会出现org.apache.lucene.store.LockObtainFailedException: Lock obtain timed out: NativeFSLock@E:\indexDir\write.lock的一场，所以对于一个索引库，只能有一个打开IndexWtriter操作他，如果打开了多个，就会有上面的异常。