Lucene入门及实际项目应用场景
Lucene入门及实际项目应用场景
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简介
1.1 什么是lucene？
Lucene是一个开源的使用java语言编写的全文搜索引擎开发包，可以融入到自己的项目中来实现增加索引和搜索功能，其实就是一款高性能的、可扩展的信息检索工具库。和其他开源软件一样，有着与生俱来的优点：功能和结构的透明性、功能强大且具有较强的扩展性、技术社区的强大支持同时也方便技术交流。Lucene只是一个搜索的核心库，并不提供具体的实现，但它的应用十分广泛，Solr、ElasticSearch 、Katta等底层用的都是Lucene。其特点：API简单，易于学习（但是不同的版本API差别较大）。
Lucene的原理：是倒排序索引。
那么到底什么是倒排序索引，什么又是正排序索引呢？
上代码：
- 需要导入的pom.xml依赖
4.0.0
com.javaxl
javaxl_lunece_freemarker
war
0.0.1-SNAPSHOT
javaxl_lunece_freemarker Maven Webapp
http://maven.apache.org
4.5.2
1.10.1
5.3.1
2.10.3
4.12
1.2.16
5.1.44
1.2.47
2.5.16
4.0.1
1.2
1.1.2
8.0.47
junit
junit
${junit.version}
test
mysql
mysql-connector-java
${mysql.version}
org.apache.httpcomponents
httpclient
${httpclient.version}
org.jsoup
jsoup
${jsoup.version}
log4j
log4j
${log4j.version}
net.sf.ehcache
ehcache
${ehcache.version}
com.alibaba
fastjson
${fastjson.version}
org.apache.struts
struts2-core
${struts2.version}
javax.servlet
javax.servlet-api
${servlet.version}
provided
org.apache.lucene
lucene-core
${lucene.version}
org.apache.lucene
lucene-queryparser
${lucene.version}
org.apache.lucene
lucene-analyzers-smartcn
${lucene.version}
org.apache.lucene
lucene-highlighter
${lucene.version}
jstl
jstl
${jstl.version}
taglibs
standard
${standard.version}
org.apache.tomcat
tomcat-jsp-api
${tomcat-jsp-api.version}
javaxl_lunece_freemarker
org.apache.maven.plugins
maven-compiler-plugin
3.7.0
1.8
1.8
UTF-8
Helloword实现
生成索引
目的：索引数据目录，在指定目录生成索引文件
1、构造方法 实例化IndexWriter
获取索引文件存放地址对象
获取输出流
设置输出流的对应配置
给输出流配置设置分词器
2、关闭索引输出流
3、索引指定路径下的所有文件
4、索引指定的文件
5、获取文档（索引文件中包含的重要信息，key-value的形式）
6、测试
lucene工具类：LuceneUtil.java
package com.javaxl.blog.util;
import java.io.IOException;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.highlight.Formatter;
import org.apache.lucene.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.QueryTermScorer;
import org.apache.lucene.search.highlight.Scorer;
import org.apache.lucene.search.highlight.SimpleFragmenter;
import org.apache.lucene.search.highlight.SimpleHTMLFormatter;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.store.RAMDirectory;
/**
* lucene工具类
* @author Administrator
*
*/
public class LuceneUtil {
/**
* 获取索引文件存放的文件夹对象
*
* @param path
* @return
*/
public static Directory getDirectory(String path) {
Directory directory = null;
try {
directory = FSDirectory.open(Paths.get(path));
} catch (IOException e) {
e.printStackTrace();
}
return directory;
}
/**
* 索引文件存放在内存
*
* @return
*/
public static Directory getRAMDirectory() {
Directory directory = new RAMDirectory();
return directory;
}
/**
* 文件夹读取对象
*
* @param directory
* @return
*/
public static DirectoryReader getDirectoryReader(Directory directory) {
DirectoryReader reader = null;
try {
reader = DirectoryReader.open(directory);
} catch (IOException e) {
e.printStackTrace();
}
return reader;
}
/**
* 文件索引对象
*
* @param reader
* @return
*/
public static IndexSearcher getIndexSearcher(DirectoryReader reader) {
IndexSearcher indexSearcher = new IndexSearcher(reader);
return indexSearcher;
}
/**
* 写入索引对象
*
* @param directory
* @param analyzer
* @return
*/
public static IndexWriter getIndexWriter(Directory directory, Analyzer analyzer)
{
IndexWriter iwriter = null;
try {
IndexWriterConfig config = new IndexWriterConfig(analyzer);
config.setOpenMode(OpenMode.CREATE_OR_APPEND);
// Sort sort=new Sort(new SortField("content", Type.STRING));
// config.setIndexSort(sort);//排序
config.setCommitOnClose(true);
// 自动提交
// config.setMergeScheduler(new ConcurrentMergeScheduler());
// config.setIndexDeletionPolicy(new
// SnapshotDeletionPolicy(NoDeletionPolicy.INSTANCE));
iwriter = new IndexWriter(directory, config);
} catch (IOException e) {
e.printStackTrace();
}
return iwriter;
}
/**
* 关闭索引文件生成对象以及文件夹对象
*
* @param indexWriter
* @param directory
*/
public static void close(IndexWriter indexWriter, Directory directory) {
if (indexWriter != null) {
try {
indexWriter.close();
} catch (IOException e) {
indexWriter = null;
}
}
if (directory != null) {
try {
directory.close();
} catch (IOException e) {
directory = null;
}
}
}
/**
* 关闭索引文件读取对象以及文件夹对象
*
* @param reader
* @param directory
*/
public static void close(DirectoryReader reader, Directory directory) {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
reader = null;
}
}
if (directory != null) {
try {
directory.close();
} catch (IOException e) {
directory = null;
}
}
}
/**
* 高亮标签
*
* @param query
* @param fieldName
* @return
*/
public static Highlighter getHighlighter(Query query, String fieldName)
{
Formatter formatter = new SimpleHTMLFormatter("", "");
Scorer fragmentScorer = new QueryTermScorer(query, fieldName);
Highlighter highlighter = new Highlighter(formatter, fragmentScorer);
highlighter.setTextFragmenter(new SimpleFragmenter(200));
return highlighter;
}
}
IndexCreate.java
package com.javaxl.lucene;
import java.io.File;
import java.io.FileReader;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.FSDirectory;
/**
* 配合Demo1.java进行lucene的helloword实现
* @author Administrator
*
*/
public class IndexCreate {
private IndexWriter indexWriter;
/**
* 1、构造方法 实例化IndexWriter
* @param indexDir
* @throws Exception
*/
public IndexCreate(String indexDir) throws Exception{
// 获取索引文件的存放地址对象
FSDirectory dir = FSDirectory.open(Paths.get(indexDir));
// 标准分词器（针对英文）
Analyzer analyzer = new StandardAnalyzer();
// 索引输出流配置对象
IndexWriterConfig conf = new IndexWriterConfig(analyzer);
indexWriter = new IndexWriter(dir, conf);
}
/**
* 2、关闭索引输出流
* @throws Exception
*/
public void closeIndexWriter() throws Exception{
indexWriter.close();
}
/**
* 3、索引指定路径下的所有文件
* @param dataDir
* @return
* @throws Exception
*/
public int index(String dataDir) throws Exception{
File[] files = new File(dataDir).listFiles();
for (File file : files) {
indexFile(file);
}
return indexWriter.numDocs();
}
/**
* 4、索引指定的文件
* @param file
* @throws Exception
*/
private void indexFile(File file) throws Exception{
System.out.println("被索引文件的全路径："+file.getCanonicalPath());
Document doc = getDocument(file);
indexWriter.addDocument(doc);
}
/**
* 5、获取文档（索引文件中包含的重要信息，key-value的形式）
* @param file
* @return
* @throws Exception
*/
private Document getDocument(File file) throws Exception{
Document doc = new Document();
doc.add(new TextField("contents", new FileReader(file)));
// Field.Store.YES是否存储到硬盘
doc.add(new TextField("fullPath", file.getCanonicalPath(),Field.Store.YES));
doc.add(new TextField("fileName", file.getName(),Field.Store.YES));
return doc;
}
}
使用索引
从索引文件中拿数据
1、获取输入流（通过dirReader）
2、获取索引搜索对象（通过输入流来拿）
3、获取查询对象（通过查询解析器来获取，解析器是通过分词器获取）
4、获取包含关键字排前面的文档对象集合
5、可以获取对应文档的内容
IndexUse.java
package com.javaxl.lucene;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.queryparser.classic.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.store.FSDirectory;
/**
* 配合Demo2.java进行lucene的helloword实现
* @author Administrator
*
*/
public class IndexUse {
/**
* 通过关键字在索引目录中查询
* @param indexDir 索引文件所在目录
* @param q 关键字
*/
public static void search(String indexDir, String q) throws Exception{
FSDirectory indexDirectory = FSDirectory.open(Paths.get(indexDir));
// 注意:索引输入流不是new出来的，是通过目录读取工具类打开的
IndexReader indexReader = DirectoryReader.open(indexDirectory);
// 获取索引搜索对象
IndexSearcher indexSearcher = new IndexSearcher(indexReader);
Analyzer analyzer = new StandardAnalyzer();
QueryParser queryParser = new QueryParser("contents", analyzer);
// 获取符合关键字的查询对象
Query query = queryParser.parse(q);
long start=System.currentTimeMillis();
// 获取关键字出现的前十次
TopDocs topDocs = indexSearcher.search(query , 10);
long end=System.currentTimeMillis();
System.out.println("匹配 "+q+" ，总共花费"+(end-start)+"毫秒"+"查询到"+topDocs.totalHits+"个记录");
for (ScoreDoc scoreDoc : topDocs.scoreDocs) {
int docID = scoreDoc.doc;
// 索引搜索对象通过文档下标获取文档
Document doc = indexSearcher.doc(docID);
System.out.println("通过索引文件："+doc.get("fullPath")+"拿数据");
}
indexReader.close();
}
}
索引测试
package com.javaxl.lucene;
/**
* 查询索引测试
* @author Administrator
*
*/
public class Demo2 {
public static void main(String[] args) {
String indexDir = "E:\\temp\\T224\\lucene\\demo1";
String q = "EarlyTerminating-Collector";
try {
IndexUse.search(indexDir, q);
} catch (Exception e) {
e.printStackTrace();
}
}
}
构建索引
Demo3.java
package com.javaxl.lucene;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.Term;
import org.apache.lucene.store.FSDirectory;
import org.junit.Before;
import org.junit.Test;
/**
* 构建索引
* 对索引的增删改
* @author Administrator
*
*/
public class Demo3 {
private String ids[]={"1","2","3"};
private String citys[]={"qingdao","nanjing","shanghai"};
private String descs[]={
"Qingdao is a beautiful city.",
"Nanjing is a city of culture.",
"Shanghai is a bustling city."
};
private FSDirectory dir;
/**
* 每次都生成索引文件
* @throws Exception
*/
@Before
public void setUp() throws Exception {
dir = FSDirectory.open(Paths.get("E:\\temp\\T224\\lucene\\demo2\\indexDir"));
IndexWriter indexWriter = getIndexWriter();
for (int i = 0; i < ids.length; i++) {
Document doc = new Document();
doc.add(new StringField("id", ids[i], Field.Store.YES));
doc.add(new StringField("city", citys[i], Field.Store.YES));
doc.add(new TextField("desc", descs[i], Field.Store.NO));
indexWriter.addDocument(doc);
}
indexWriter.close();
}
/**
* 获取索引输出流
* @return
* @throws Exception
*/
private IndexWriter getIndexWriter() throws Exception{
Analyzer analyzer = new StandardAnalyzer();
IndexWriterConfig conf = new IndexWriterConfig(analyzer);
return new IndexWriter(dir, conf );
}
/**
* 测试写了几个索引文件
* @throws Exception
*/
@Test
public void getWriteDocNum() throws Exception {
IndexWriter indexWriter = getIndexWriter();
System.out.println("索引目录下生成"+indexWriter.numDocs()+"个索引文件");
}
/**
* 打上标记，该索引实际并未删除
* @throws Exception
*/
@Test
public void deleteDocBeforeMerge() throws Exception {
IndexWriter indexWriter = getIndexWriter();
System.out.println("最大文档数："+indexWriter.maxDoc());
indexWriter.deleteDocuments(new Term("id", "1"));
indexWriter.commit();
System.out.println("最大文档数："+indexWriter.maxDoc());
System.out.println("实际文档数："+indexWriter.numDocs());
indexWriter.close();
}
/**
* 对应索引文件已经删除,但是该版本的分词会保留
* @throws Exception
*/
@Test
public void deleteDocAfterMerge() throws Exception {
// https://blog.csdn.net/asdfsadfasdfsa/article/details/78820030
// org.apache.lucene.store.LockObtainFailedException: Lock held by this virtual machine:indexWriter是单例的、线程安全的，不允许打开多个。
IndexWriter indexWriter = getIndexWriter();
System.out.println("最大文档数："+indexWriter.maxDoc());
indexWriter.deleteDocuments(new Term("id", "1"));
indexWriter.forceMergeDeletes(); //强制删除
indexWriter.commit();
System.out.println("最大文档数："+indexWriter.maxDoc());
System.out.println("实际文档数："+indexWriter.numDocs());
indexWriter.close();
}
/**
* 测试更新索引
* @throws Exception
*/
@Test
public void testUpdate()throws Exception{
IndexWriter writer=getIndexWriter();
Document doc=new Document();
doc.add(new StringField("id", "1", Field.Store.YES));
doc.add(new StringField("city","qingdao",Field.Store.YES));
doc.add(new TextField("desc", "dsss is a city.", Field.Store.NO));
writer.updateDocument(new Term("id","1"), doc);
writer.close();
}
}
注意：5.3的版本修改前的分词不会消失。
文档域加权
Demo4.java:
package com.javaxl.lucene;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
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.junit.Before;
import org.junit.Test;
/**
* 文档域加权
* @author Administrator
*
*/
public class Demo4 {
private String ids[]={"1","2","3","4"};
private String authors[]={"Jack","Marry","John","Json"};
private String positions[]={"accounting","technician","salesperson","boss"};
private String titles[]={"Java is a good language.","Java is a cross platform language","Java powerful","You should learn java"};
private String contents[]={
"If possible, use the same JRE major version at both index and search time.",
"When upgrading to a different JRE major version, consider re-indexing. ",
"Different JRE major versions may implement different versions of Unicode,",
"For example: with Java 1.4, `LetterTokenizer` will split around the character U+02C6,"
};
private Directory dir;//索引文件目录
@Before
public void setUp()throws Exception {
dir = FSDirectory.open(Paths.get("E:\\temp\\T224\\lucene\\demo3\\indexDir"));
IndexWriter writer = getIndexWriter();
for (int i = 0; i < authors.length; i++) {
Document doc = new Document();
doc.add(new StringField("id", ids[i], Field.Store.YES));
doc.add(new StringField("author", authors[i], Field.Store.YES));
doc.add(new StringField("position", positions[i], Field.Store.YES));
TextField textField = new TextField("title", titles[i], Field.Store.YES);
// Json投钱做广告，把排名刷到第一了
// if("boss".equals(positions[i])) {
// textField.setBoost(2f);//设置权重，默认为1
// }
doc.add(textField);
// TextField会分词，StringField不会分词
doc.add(new TextField("content", contents[i], Field.Store.NO));
writer.addDocument(doc);
}
writer.close();
}
private IndexWriter getIndexWriter() throws Exception{
Analyzer analyzer = new StandardAnalyzer();
IndexWriterConfig conf = new IndexWriterConfig(analyzer);
return new IndexWriter(dir, conf);
}
@Test
public void index() throws Exception{
IndexReader reader = DirectoryReader.open(dir);
IndexSearcher searcher = new IndexSearcher(reader);
String fieldName = "title";
String keyWord = "java";
Term t = new Term(fieldName, keyWord);
Query query = new TermQuery(t);
TopDocs hits = searcher.search(query, 10);
System.out.println("关键字：‘"+keyWord+"’命中了"+hits.totalHits+"次");
for (ScoreDoc scoreDoc : hits.scoreDocs) {
Document doc = searcher.doc(scoreDoc.doc);
System.out.println(doc.get("author"));
}
}
}
索引搜索功能
特定项搜索
Demo5.java:
package com.javaxl.lucene;
import java.io.IOException;
import java.nio.file.Paths;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.queryparser.classic.ParseException;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.NumericRangeQuery;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.FSDirectory;
import org.junit.Before;
import org.junit.Test;
/**
* 特定项搜索
* 查询表达式（queryParser）
* @author Administrator
*
*/
public class Demo5 {
@Before
public void setUp() {
// 索引文件将要存放的位置
String indexDir = "E:\\temp\\T224\\lucene\\demo4";
// 数据源地址
String dataDir = "E:\\temp\\T224\\lucene\\demo4\\data";
IndexCreate ic = null;
try {
ic = new IndexCreate(indexDir);
long start = System.currentTimeMillis();
int num = ic.index(dataDir);
long end = System.currentTimeMillis();
System.out.println("检索指定路径下" + num + "个文件，一共花费了" + (end - start) + "毫秒");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
ic.closeIndexWriter();
} catch (Exception e) {
e.printStackTrace();
}
}
}
/**
* 特定项搜索
*/
@Test
public void testTermQuery() {
String indexDir = "E:\\temp\\T224\\lucene\\demo4";
String fld = "contents";
String text = "indexformattoooldexception";
// 特定项片段名和关键字
Term t = new Term(fld , text);
TermQuery tq = new TermQuery(t );
try {
FSDirectory indexDirectory = FSDirectory.open(Paths.get(indexDir));
// 注意:索引输入流不是new出来的，是通过目录读取工具类打开的
IndexReader indexReader = DirectoryReader.open(indexDirectory);
// 获取索引搜索对象
IndexSearcher is = new IndexSearcher(indexReader);
TopDocs hits = is.search(tq, 100);
// System.out.println(hits.totalHits);
for(ScoreDoc scoreDoc: hits.scoreDocs) {
Document doc = is.doc(scoreDoc.doc);
System.out.println("文件"+doc.get("fullPath")+"中含有该关键字");
}
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 查询表达式（queryParser）
*/
@Test
public void testQueryParser() {
String indexDir = "E:\\temp\\T224\\lucene\\demo4";
// 获取查询解析器（通过哪种分词器去解析哪种片段）
QueryParser queryParser = new QueryParser("contents", new StandardAnalyzer());
try {
FSDirectory indexDirectory = FSDirectory.open(Paths.get(indexDir));
// 注意:索引输入流不是new出来的，是通过目录读取工具类打开的
IndexReader indexReader = DirectoryReader.open(indexDirectory);
// 获取索引搜索对象
IndexSearcher is = new IndexSearcher(indexReader);
// 由解析器去解析对应的关键字
TopDocs hits = is.search(queryParser.parse("indexformattoooldexception") , 100);
for(ScoreDoc scoreDoc: hits.scoreDocs) {
Document doc = is.doc(scoreDoc.doc);
System.out.println("文件"+doc.get("fullPath")+"中含有该关键字");
}
} catch (IOException e) {
e.printStackTrace();
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Lucene查看工具
其他查询方法
指定数字范围查询（numbericRangeQuery）
Demo6.java
package com.javaxl.lucene;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.IntField;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
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.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.NumericRangeQuery;
import org.apache.lucene.search.PrefixQuery;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.FSDirectory;
import org.junit.Before;
import org.junit.Test;
/**
* 指定数字范围查询
* 指定字符串开头字母查询（prefixQuery）
* @author Administrator
*
*/
public class Demo6 {
private int ids[]={1,2,3};
private String citys[]={"qingdao","nanjing","shanghai"};
private String descs[]={
"Qingdao is a beautiful city.",
"Nanjing is a city of culture.",
"Shanghai is a bustling city."
};
private FSDirectory dir;
/**
* 每次都生成索引文件
* @throws Exception
*/
@Before
public void setUp() throws Exception {
dir = FSDirectory.open(Paths.get("E:\\temp\\T224\\lucene\\demo2\\indexDir"));
IndexWriter indexWriter = getIndexWriter();
for (int i = 0; i < ids.length; i++) {
Document doc = new Document();
doc.add(new IntField("id", ids[i], Field.Store.YES));
doc.add(new StringField("city", citys[i], Field.Store.YES));
doc.add(new TextField("desc", descs[i], Field.Store.NO));
indexWriter.addDocument(doc);
}
indexWriter.close();
}
/**
* 获取索引输出流
* @return
* @throws Exception
*/
private IndexWriter getIndexWriter() throws Exception{
Analyzer analyzer = new StandardAnalyzer();
IndexWriterConfig conf = new IndexWriterConfig(analyzer);
return new IndexWriter(dir, conf );
}
/**
* 指定数字范围查询
* @throws Exception
*/
@Test
public void testNumericRangeQuery()throws Exception{
IndexReader reader = DirectoryReader.open(dir);
IndexSearcher is = new IndexSearcher(reader);
NumericRangeQuery query=NumericRangeQuery.newIntRange("id", 1, 2, true, true);
TopDocs hits=is.search(query, 10);
for(ScoreDoc scoreDoc:hits.scoreDocs){
Document doc=is.doc(scoreDoc.doc);
System.out.println(doc.get("id"));
System.out.println(doc.get("city"));
System.out.println(doc.get("desc"));
}
}
/**
* 指定字符串开头字母查询（prefixQuery）
* @throws Exception
*/
@Test
public void testPrefixQuery()throws Exception{
IndexReader reader = DirectoryReader.open(dir);
IndexSearcher is = new IndexSearcher(reader);
//头部查询
PrefixQuery query=new PrefixQuery(new Term("city","n"));
TopDocs hits=is.search(query, 10);
for(ScoreDoc scoreDoc:hits.scoreDocs){
Document doc=is.doc(scoreDoc.doc);
System.out.println(doc.get("id"));
System.out.println(doc.get("city"));
System.out.println(doc.get("desc"));
}
}
@Test
public void testBooleanQuery()throws Exception{
IndexReader reader = DirectoryReader.open(dir);
IndexSearcher is = new IndexSearcher(reader);
NumericRangeQuery query1=NumericRangeQuery.newIntRange("id", 1, 2, true, true);
PrefixQuery query2=new PrefixQuery(new Term("city","n"));
BooleanQuery.Builder booleanQuery=new BooleanQuery.Builder();
booleanQuery.add(query1,BooleanClause.Occur.MUST);
booleanQuery.add(query2,BooleanClause.Occur.MUST);
TopDocs hits=is.search(booleanQuery.build(), 10);
for(ScoreDoc scoreDoc:hits.scoreDocs){
Document doc=is.doc(scoreDoc.doc);
System.out.println(doc.get("id"));
System.out.println(doc.get("city"));
System.out.println(doc.get("desc"));
}
}
}
指定字符串开头字母查询（prefixQuery）
组合查询（booleanQuery）重点
Must、must not、should
高亮显示的步奏：
1、通过查询对象，获取查询得分对象
2、通过得分对象，获取对应的片段
3、实例化一个html格式化对象
4、通过html格式化实例和查询得分实例，来实例化Lucene提供的高亮显示类对象。
5、将前面获取到的得分片段，设置到高亮显示的的实例对象中。
6、通过分词器获取TokenStream令牌流对象
7、通过令牌和原有的片段，去拿高亮展示后的片段
Demo7.java
package com.javaxl.lucene;
import java.io.StringReader;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.IntField;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.queryparser.classic.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.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.QueryScorer;
import org.apache.lucene.search.highlight.SimpleHTMLFormatter;
import org.apache.lucene.search.highlight.SimpleSpanFragmenter;
import org.apache.lucene.store.FSDirectory;
import org.junit.Before;
import org.junit.Test;
public class Demo7 {
private Integer ids[] = { 1, 2, 3 };
private String citys[] = { "青岛", "南京", "上海" };
// private String descs[]={
// "青岛是个美丽的城市。",
// "南京是个有文化的城市。",
// "上海市个繁华的城市。"
// };
private String descs[] = { "青岛是个美丽的城市。",
"南京是一个文化的城市南京，简称宁，是江苏省会，地处中国东部地区，长江下游，濒江近海。全市下辖11个区，总面积6597平方公里，2013年建成区面积752.83平方公里，常住人口818.78万，其中城镇人口659.1万人。[1-4] “江南佳丽地，金陵帝王州”，南京拥有着6000多年文明史、近2600年建城史和近500年的建都史，是中国四大古都之一，有“六朝古都”、“十朝都会”之称，是中华文明的重要发祥地，历史上曾数次庇佑华夏之正朔，长期是中国南方的政治、经济、文化中心，拥有厚重的文化底蕴和丰富的历史遗存。[5-7] 南京是国家重要的科教中心，自古以来就是一座崇文重教的城市，有“天下文枢”、“东南第一学”的美誉。截至2013年，南京有高等院校75所，其中211高校8所，仅次于北京上海；国家重点实验室25所、国家重点学科169个、两院院士83人，均居中国第三。[8-10]",
"上海市个繁华的城市。" };
private FSDirectory dir;
/**
* 每次都生成索引文件
*
* @throws Exception
*/
@Before
public void setUp() throws Exception {
dir = FSDirectory.open(Paths.get("E:\\temp\\T224\\lucene\\demo2\\indexDir"));
IndexWriter indexWriter = getIndexWriter();
for (int i = 0; i < ids.length; i++) {
Document doc = new Document();
doc.add(new IntField("id", ids[i], Field.Store.YES));
doc.add(new StringField("city", citys[i], Field.Store.YES));
doc.add(new TextField("desc", descs[i], Field.Store.YES));
indexWriter.addDocument(doc);
}
indexWriter.close();
}
/**
* 获取索引输出流
*
* @return
* @throws Exception
*/
private IndexWriter getIndexWriter() throws Exception {
// Analyzer analyzer = new StandardAnalyzer();
Analyzer analyzer = new SmartChineseAnalyzer();
IndexWriterConfig conf = new IndexWriterConfig(analyzer);
return new IndexWriter(dir, conf);
}
/**
* luke查看索引生成
*
* @throws Exception
*/
@Test
public void testIndexCreate() throws Exception {
}
/**
* 测试高亮
*
* @throws Exception
*/
@Test
public void testHeight() throws Exception {
IndexReader reader = DirectoryReader.open(dir);
IndexSearcher searcher = new IndexSearcher(reader);
SmartChineseAnalyzer analyzer = new SmartChineseAnalyzer();
QueryParser parser = new QueryParser("desc", analyzer);
// Query query = parser.parse("南京文化");
Query query = parser.parse("南京文明");
TopDocs hits = searcher.search(query, 100);
// 查询得分项
QueryScorer queryScorer = new QueryScorer(query);
// 得分项对应的内容片段
SimpleSpanFragmenter fragmenter = new SimpleSpanFragmenter(queryScorer);
// 高亮显示的样式
SimpleHTMLFormatter htmlFormatter = new SimpleHTMLFormatter("", "");
// 高亮显示对象
Highlighter highlighter = new Highlighter(htmlFormatter, queryScorer);
// 设置需要高亮显示对应的内容片段
highlighter.setTextFragmenter(fragmenter);
for (ScoreDoc scoreDoc : hits.scoreDocs) {
Document doc = searcher.doc(scoreDoc.doc);
String desc = doc.get("desc");
if (desc != null) {
// tokenstream是从doucment的域（field)中抽取的一个个分词而组成的一个数据流，用于分词。
TokenStream tokenStream = analyzer.tokenStream("desc", new StringReader(desc));
System.out.println("高亮显示的片段：" + highlighter.getBestFragment(tokenStream, desc));
}
System.out.println("所有内容：" + desc);
}
}
}
BlogAction.java
package com.javaxl.blog.web;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.queryparser.classic.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.search.highlight.Highlighter;
import org.apache.lucene.store.Directory;
import org.apache.struts2.ServletActionContext;
import com.javaxl.blog.dao.BlogDao;
import com.javaxl.blog.util.LuceneUtil;
import com.javaxl.blog.util.PropertiesUtil;
import com.javaxl.blog.util.StringUtils;
/**
* IndexReader
* IndexSearcher
* Highlighter
* @author Administrator
*
*/
public class BlogAction {
private String title;
private BlogDao blogDao = new BlogDao();
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String list() {
try {
HttpServletRequest request = ServletActionContext.getRequest();
if (StringUtils.isBlank(title)) {
List> blogList = this.blogDao.list(title, null);
request.setAttribute("blogList", blogList);
}else {
Directory directory = LuceneUtil.getDirectory(PropertiesUtil.getValue("indexPath"));
DirectoryReader reader = LuceneUtil.getDirectoryReader(directory);
IndexSearcher searcher = LuceneUtil.getIndexSearcher(reader);
SmartChineseAnalyzer analyzer = new SmartChineseAnalyzer();
// 拿一句话到索引目中的索引文件中的词库进行关键词碰撞
Query query = new QueryParser("title", analyzer).parse(title);
Highlighter highlighter = LuceneUtil.getHighlighter(query, "title");
TopDocs topDocs = searcher.search(query , 100);
//处理得分命中的文档
List> blogList = new ArrayList<>();
Map map = null;
ScoreDoc[] scoreDocs = topDocs.scoreDocs;
for (ScoreDoc scoreDoc : scoreDocs) {
map = new HashMap<>();
Document doc = searcher.doc(scoreDoc.doc);
map.put("id", doc.get("id"));
String titleHighlighter = doc.get("title");
if(StringUtils.isNotBlank(titleHighlighter)) {
titleHighlighter = highlighter.getBestFragment(analyzer, "title", titleHighlighter);
}
map.put("title", titleHighlighter);
map.put("url", doc.get("url"));
blogList.add(map);
}
request.setAttribute("blogList", blogList);
}
} catch (Exception e) {
e.printStackTrace();
}
return "blogList";
}
}
IndexStarter.java
package com.javaxl.blog.web;
import java.io.IOException;
import java.nio.file.Paths;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import com.javaxl.blog.dao.BlogDao;
import com.javaxl.blog.util.PropertiesUtil;
/**
* 构建lucene索引
* @author Administrator
* 1。构建索引 IndexWriter
* 2、读取索引文件，获取命中片段
* 3、使得命中片段高亮显示
*
*/
public class IndexStarter {
private static BlogDao blogDao = new BlogDao();
public static void main(String[] args) {
IndexWriterConfig conf = new IndexWriterConfig(new SmartChineseAnalyzer());
Directory d;
IndexWriter indexWriter = null;
try {
d = FSDirectory.open(Paths.get(PropertiesUtil.getValue("indexPath")));
indexWriter = new IndexWriter(d , conf );
// 为数据库中的所有数据构建索引
List> list = blogDao.list(null, null);
for (Map map : list) {
Document doc = new Document();
doc.add(new StringField("id", (String) map.get("id"), Field.Store.YES));
// TextField用于对一句话分词处理 java培训机构
doc.add(new TextField("title", (String) map.get("title"), Field.Store.YES));
doc.add(new StringField("url", (String) map.get("url"), Field.Store.YES));
indexWriter.addDocument(doc);
}
} catch (IOException e) {
e.printStackTrace();
} catch (InstantiationException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}finally {
try {
if(indexWriter!= null) {
indexWriter.close();
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
