lucene索引创建与查询入门例子

一、创建索引

import java.io.File;
import java.io.FileReader;
import java.util.Date;


import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.DateTools;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.SimpleFSDirectory;
import org.apache.lucene.util.Version;


public class Indexer {


/**
* @param args
*/
public static void main(String[] args) throws Throwable{
//保存索引文件的地方
String indexDir = "F:\\testIndex";
//将要搜索TXT文件的地方
String dateDir = "F:\\testDoc";
IndexWriter indexWriter = null;
//创建Directory对象
Directory dir = new SimpleFSDirectory(new File(indexDir));
//创建IndexWriter对象,第一个参数是Directory,第二个是分词器,第三个表示是否是创建,如果为false为在此基础上面修改,第四表示表示分词的最大值，比如说new MaxFieldLength(2)，就表示两个字一分，一般用IndexWriter.MaxFieldLength.LIMITED
indexWriter = new IndexWriter(dir,new StandardAnalyzer(Version.LUCENE_36),true,IndexWriter.MaxFieldLength.UNLIMITED);
File[] files = new File(dateDir).listFiles();
for (int i = 0; i < files.length; i++) {
Document doc = new Document();
//创建Field对象，并放入doc对象中
doc.add(new Field("contents", new FileReader(files[i])));
doc.add(new Field("filename", files[i].getName(),
Field.Store.YES, Field.Index.NOT_ANALYZED));
doc.add(new Field("indexDate",DateTools.dateToString(new Date(), DateTools.Resolution.DAY),Field.Store.YES,Field.Index.NOT_ANALYZED));
//写入IndexWriter
indexWriter.addDocument(doc);
}
//查看IndexWriter里面有多少个索引
System.out.println("numDocs"+indexWriter.numDocs());
indexWriter.close();

}


}

二、查询索引

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


import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.FieldSelector;
import org.apache.lucene.document.MapFieldSelector;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.FilteredQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.QueryWrapperFilter;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.SimpleFSDirectory;
import org.apache.lucene.util.Version;


public class Searcher {


/**
* @param args
*/
public static void main(String[] args) throws Throwable{
//保存索引文件的地方
String indexDir = "F:\\testIndex";
Directory dir = new SimpleFSDirectory(new File(indexDir));
//创建 IndexSearcher对象，相比IndexWriter对象，这个参数就要提供一个索引的目录就行了
IndexSearcher indexSearch = new IndexSearcher(dir);
//创建QueryParser对象,第一个参数表示Lucene的版本,第二个表示搜索Field的字段,第三个表示搜索使用分词器
QueryParser queryParser = new QueryParser(Version.LUCENE_36,
"contents", new StandardAnalyzer(Version.LUCENE_36));
//生成Query对象
Query query = queryParser.parse("contents:book ");
Query queryFilter = queryParser.parse("indexDate:20130304");

Filter filter = new QueryWrapperFilter(queryFilter);
//在结果中找
query = new FilteredQuery(query,filter);
filter = new QueryWrapperFilter(queryParser.parse("filename:na*"));
//搜索结果 TopDocs里面有scoreDocs[]数组，里面保存着索引值
TopDocs hits = indexSearch.search(query,filter, 10);
//hits.totalHits表示一共搜到多少个
System.out.println("找到了"+hits.totalHits+"个");
//循环hits.scoreDocs数据，并使用indexSearch.doc方法把Document还原，再拿出对应的字段的值
for (int i = 0; i < hits.scoreDocs.length; i++) {
ScoreDoc sdoc = hits.scoreDocs[i];
Document doc = indexSearch.doc(sdoc.doc);
// List<String> list = new ArrayList<String>();
// list.add("indexDate");
// //添加选择器，可选择加载哪些Field
// FieldSelector selector = new MapFieldSelector(list);
// doc = indexSearch.doc(sdoc.doc, selector);
System.out.println(doc.get("filename"));
// System.out.println(doc.get("contents"));
// System.out.println(doc.get("indexDate"));
// for(Fieldable str :doc.getFields()){
// System.out.println(str);
// }
//
// System.out.println(sdoc);
}
indexSearch.close();
}


}