Luke
使用Luke可以查看分词信息,其下载地址为:http://code.google.com/p/luke/
注意:每一个Lucene版本都会有一个相应的Luke文件
用法为双击lukeall-3.5.0.jar
或命令执行java -jar lukeall-3.5.0.jar
然后选择索引的存放目录,再点击OK即可
如果我们的索引有改变,可以点击右侧的Re-open
按钮重新载入索引
Luke界面右下角的Top ranking terms
窗口中显示的就是分词信息(其中Rank列表示出现频率)
Luke菜单下的Documents
选项卡中显示的就是文档信息,我们可以根据文档序号来浏览(点击向左和向右的方向箭头)
Luke菜单下的Search
选项卡中可以根据我们输入的表达式来查文档内容
比如在Enter search expression here:
输入content:my
,再在右侧点击一个黑色粗体字的Search大按钮即可
代码
下面演示的是Lucene-3.6.2
中针对索引文件增删改查的操作方式
package com.xuanyuv.lucene;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.NumericField;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;
/**
* Lucene系列第02节之操作索引
* Created by 玄玉<https://www.xuanyuv.com/> on 2013/08/18 15:48.
*/
public class HelloIndex {
/*
* 定义一组数据,用来演示搜索(这里有一封邮件为例)
* 假设每一个变量代表一个Document,这里就定义了6个Document
*/
//邮件编号
private String[] ids = {"1", "2", "3", "4", "5", "6"};
//邮件主题
private String[] names = {"Michael", "Scofield", "Tbag", "Jack", "Jade", "Xuanyu"};
//邮件地址
private String[] emails = {"aa@xuanyuv.us", "bb@xuanyuv.cn", "cc@xuanyuv.cc", "dd@xuanyuv.tw", "ee@xuanyuv.hk", "ff@xuanyuv.me"};
//邮件内容
private String[] contents = {"my blog", "my website", "my name", "I am JavaDeveloper", "I am from Haerbin", "I like Lucene"};
//邮件附件(为数字和日期加索引,与,字符串加索引的方式不同)
private int[] attachs = {9,3,5,4,1,2};
//邮件日期
private Date[] dates = new Date[ids.length];
//它的创建是比较耗时耗资源的,所以这里只让它创建一次,此时reader处于整个生命周期中,实际应用中也可能直接放到ApplicationContext里面
private static IndexReader reader = null;
private Directory directory = null;
public HelloIndex(){
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
try {
dates[0] = sdf.parse("20120601");
dates[1] = sdf.parse("20120603");
dates[2] = sdf.parse("20120605");
dates[3] = sdf.parse("20120607");
dates[4] = sdf.parse("20120609");
dates[5] = sdf.parse("20120611");
directory = FSDirectory.open(new File("myExample/02_index/"));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 获取IndexReader实例
*/
private IndexReader getIndexReader(){
try {
if(null == reader){
reader = IndexReader.open(directory);
}else{
//if the index was changed since the provided reader was opened, open and return a new reader; else,return null
//如果当前reader在打开期间index发生改变,则打开并返回一个新的IndexReader,否则返回null
IndexReader ir = IndexReader.openIfChanged(reader);
if(null != ir){
reader.close(); //关闭原reader
reader = ir; //赋予新reader
}
}
return reader;
}catch(Exception e) {
e.printStackTrace();
}
return null; //发生异常则返回null
}
/**
* 通过IndexReader获取文档数量
*/
public void getDocsCount(){
System.out.println("maxDocs:" + this.getIndexReader().maxDoc());
System.out.println("numDocs:" + this.getIndexReader().numDocs());
System.out.println("deletedDocs:" + this.getIndexReader().numDeletedDocs());
}
/**
* 创建索引
*/
public void createIndex(){
IndexWriter writer = null;
Document doc = null;
try{
writer = new IndexWriter(directory, new IndexWriterConfig(Version.LUCENE_36, new StandardAnalyzer(Version.LUCENE_36)));
//创建索引之前,先把文档清空掉
writer.deleteAll();
//遍历ID来创建文档
for(int i=0; i<ids.length; i++){
doc = new Document();
doc.add(new Field("id", ids[i], Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS));
doc.add(new Field("name", names[i], Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS));
doc.add(new Field("email", emails[i], Field.Store.YES, Field.Index.NOT_ANALYZED));
doc.add(new Field("content", contents[i], Field.Store.NO, Field.Index.ANALYZED));
//为数字加索引(第三个参数指定是否索引)
doc.add(new NumericField("attach", Field.Store.YES, true).setIntValue(attachs[i]));
//为日期加索引
doc.add(new NumericField("date", Field.Store.YES, true).setLongValue(dates[i].getTime()));
//建立索引时加权(定义排名规则,即加权,这里是为指定邮件名结尾的emails加权)
if(emails[i].endsWith("xuanyuv.com")){
doc.setBoost(2.0f);
}else if(emails[i].endsWith("xuanyuv.cn")){
//为文档加权(注意它的参数类型是Float,默认为1.0f,权值越高则排名越高,显示得就越靠前)
doc.setBoost(1.5f);
}else{
doc.setBoost(0.5f);
}
writer.addDocument(doc);
}
}catch(Exception e) {
e.printStackTrace();
}finally{
if(null != writer){
try {
writer.close();
} catch (IOException ce) {
ce.printStackTrace();
}
}
}
}
/**
* 搜索文件
*/
public void searchFile(){
IndexSearcher searcher = new IndexSearcher(this.getIndexReader());
//精确搜索:搜索"content"中包含"my"的文档
Query query = new TermQuery(new Term("content", "my"));
try{
TopDocs tds = searcher.search(query, 10);
for(ScoreDoc sd : tds.scoreDocs){
//sd.doc得到的是文档的序号
Document doc = searcher.doc(sd.doc);
//doc.getBoost()得到的权值与创建索引时设置的权值之间是不相搭的,创建索引时的权值的查看需要使用Luke工具
// 之所以这样,是因为这里的Document对象(是获取到的)与创建索引时的Document对象,不是同一个对象
//sd.score得到的是该文档的评分,该评分规则的公式是比较复杂的,它主要与文档的权值和出现次数成正比
System.out.print("("+sd.doc+"|"+doc.getBoost()+"|"+sd.score+")"+doc.get("name")+"["+doc.get("email")+"]-->");
System.out.print(doc.get("id")+","+doc.get("attach")+",");
System.out.println(new SimpleDateFormat("yyyyMMdd").format(new Date(Long.parseLong(doc.get("date")))));
}
}catch(Exception e){
e.printStackTrace();
}finally{
if(null != searcher){
try {
searcher.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/**
* 更新索引
* ----------------------------------------------------------------------
* Lucene其实并未提供更新索引的方法,这里的更新操作内部是先删除再添加的方式
* 因为Lucene认为更新索引的代价,与删除后重建索引的代价,二者是差不多的
* ----------------------------------------------------------------------
*/
public void updateIndex(){
IndexWriter writer = null;
Document doc = new Document();
try{
writer = new IndexWriter(directory, new IndexWriterConfig(Version.LUCENE_36, new StandardAnalyzer(Version.LUCENE_36)));
doc.add(new Field("id", "1111", Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS));
doc.add(new Field("name", names[0], Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS));
doc.add(new Field("email", emails[0], Field.Store.YES, Field.Index.NOT_ANALYZED));
doc.add(new Field("content", contents[0], Field.Store.NO, Field.Index.ANALYZED));
doc.add(new NumericField("attach", Field.Store.YES, true).setIntValue(attachs[0]));
doc.add(new NumericField("date", Field.Store.YES, true).setLongValue(dates[0].getTime()));
//其实它会先删除索引文档中id为1的文档,然后再将这里的doc对象重新索引,所以即便这里的1!=1111,但它并不会报错
//所以在执行完该方法后:maxDocs=7,numDocs=6,deletedDocs=1,就是因为Lucene会先删除再添加
writer.updateDocument(new Term("id","1"), doc);
}catch(Exception e) {
e.printStackTrace();
}finally{
if(null != writer){
try {
writer.close();
} catch (IOException ce) {
ce.printStackTrace();
}
}
}
}
/**
* 删除索引
* ----------------------------------------------------------------------------------------------
* 在执行完该方法后,再执行本类的searchFile()方法,得知numDocs=5,maxDocs=6,deletedDocs=1
* 这说明此时删除的文档并没有被完全删除,而是存储在一个回收站中,它是可以恢复的
* ----------------------------------------------------------------------------------------------
* 从回收站中清空索引IndexWriter
* 对于清空索引,Lucene3.5之前叫做优化,调用的是IndexWriter.optimize()方法,但该方法已被禁用
* 因为optimize时它会全部更新索引,这一过程所涉及到的负载是很大的,于是弃用了该方法,使用forceMerge代替
* 使用IndexWriter.forceMergeDeletes()方法可以强制清空回收站中的内容
* 另外IndexWriter.forceMerge(3)方法会将索引合并为3段,这3段中的被删除的数据也会被清空
* 但其在Lucene3.5之后不建议使用,因为其会消耗大量的开销,而Lucene会根据情况自动处理的
* ----------------------------------------------------------------------------------------------
*/
public void deleteIndex(){
IndexWriter writer = null;
try{
writer = new IndexWriter(directory, new IndexWriterConfig(Version.LUCENE_36, new StandardAnalyzer(Version.LUCENE_36)));
//其参数可以传Query或Term(Query指的是可以查询出一系列的结果并将其全部删掉,而Term属于精确查找)
//删除索引文档中id为1的文档
writer.deleteDocuments(new Term("id", "1"));
}catch(Exception e) {
e.printStackTrace();
}finally{
if(null != writer){
try {
writer.close();
} catch (IOException ce) {
ce.printStackTrace();
}
}
}
}
/**
* 恢复索引(建议弃用)
*/
@Deprecated
public void unDeleteIndex(){
IndexReader reader = null;
try {
//IndexReader.open(directory)此时该IndexReader默认的readOnly=true,而在恢复索引时应该指定其为非只读的
reader = IndexReader.open(directory, false);
//Deprecated. Write support will be removed in Lucene 4.0. There will be no replacement for this method.
reader.undeleteAll();
} catch (Exception e) {
e.printStackTrace();
}finally{
if(null != reader){
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
最后补充一个JUnit4.x
写的一个小测试
package com.xuanyuv.test;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import com.xuanyuv.lucene.HelloIndex;
public class HelloIndexTest {
private HelloIndex hello;
@Before
public void init(){
hello = new HelloIndex();
}
@After
public void destroy(){
hello.getDocsCount();
}
@Test
public void createIndex(){
hello.createIndex();
}
@Test
public void searchFile(){
hello.searchFile();
}
@Test
public void updateIndex(){
hello.updateIndex();
}
@Test
public void deleteIndex(){
hello.deleteIndex();
}
@Test
@SuppressWarnings("deprecation")
public void unDeleteIndex(){
hello.unDeleteIndex();
}
}