发布于 2015-05-11 10:54:32 | 166 次阅读 | 评论: 0 | 来源: 网友投递
Apache Lucene全文检索引擎工具包
Lucene是apache软件基金会4 jakarta项目组的一个子项目，是一个开放源代码的全文检索引擎工具包，即它不是一个完整的全文检索引擎，而是一个全文检索引擎的架构，提供了完整的查询引擎和索引引擎，部分文本分析引擎（英文与德文两种西方语言）。Lucene的目的是为软件开发人员提供一个简单易用的工具包，以方便的在目标系统中实现全文检索的功能，或者是以此为基础建立起完整的全文检索引擎。
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IndexReader的设计
--------------------------------------------------
IndexReader的创建需要消耗大量内存空间,
所以通过将IndexReader设计出属性值，进行一次创建
整个项目周期就只有一个IndexReader
1.// IndexReader的设计
private static IndexReader reader = null;
2.在构造方法中对IndexReader进行初始化
// 创建indexReader
reader = IndexReader.open(directory);
3.创建getSearch()方法，返回IndexSearch
private static IndexSearcher getSearch() {
return new IndexSearcher(reader);
}
4.最后在使用IndexReader完毕后，只需要关闭IndexSearch
// 最后只需要关闭search
search.close();
PS：
因此此IndexReader属于单例模式，在IndexReader过程中如果改变IndexWriter的索引，IndexReader所search出的数据将不会改变，除非重新构建一个新的IndexReader
代码优化：
// 优化
try {
if (reader == null) {
reader = IndexReader.open(directory);
//reader = IndexReader.open(directory,false); //不设置为只读的reader
} else {
// 如果Index索引改变了将返回一个新的reader，否则将返回null
IndexReader read = IndexReader.openIfChanged(reader);
if (read != null) {
//把原来的reader给close()掉
reader.close();
reader = read;
}
}
return new IndexSearcher(reader);
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
//因为此时Reader已经为全局范围，用reader也能删除文档
/*
* 使用reader删除，会立即更新索引信息(但不建议)
*/
// reader.deleteDocuments(new Term("id","1"));
// reader.close();
有时候整个项目周期中只有一个IndexWriter
这时候，IndexWriter就不能关闭
那么怎么提交呢？
使用IndexWriter.commit()方法提交对索引操作后的数据
--------------------------------------------------------
Directory的几种操作方式
--------------------------------------------------------
FSDirectory.open()。。系统会根据具体运行环境使用最佳方式打开一个Directory
new RAMDirectory()。。就是将索引存储在内存中。好处：速度快。坏处：不能持久化
RAMDirectory（Directory dir）。也可以将一个持久化好的directory放入内存中。
-------------------------------------------------------
lucene的搜索_TermRange等基本搜索
-------------------------------------------------------
1.创建IndexSearch
/*
* 创建IndexSearch的方法
*/
public IndexSearcher getSearch() {
try {
if (reader == null) {
reader = IndexReader.open(directory);
} else {
IndexReader read = IndexReader.openIfChanged(reader);
if (read != null) {
reader.close();
reader = read;
}
}
return new IndexSearcher(reader);
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
2.查询的几种
======精确查询：
IndexSearcher search = getSearch();
Query query = new TermQuery(new Term(field, name));
TopDocs tds = search.search(query, num);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
}
search.close();
======基于字符串的范围查询（TermRange）
// true表示闭区间
IndexSearcher search = getSearch();
Query query = new TermRangeQuery(field, start, end, true, true);
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
======基于数字的范围查询（NumericRangeQuery.new...)
IndexSearcher search = getSearch();
// true表示闭区间
Query query = NumericRangeQuery.newIntRange(field, start, end,true, true);
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
======PS:tds.totalHits是总记录数，与我们传入的num，没有任何关系
eg:
// 基于范围的查询(参数：传入的field，开始字符，结束字符，显示数目)
public void SearchByTermRange(String field, String start, String end,int num) {
try {
IndexSearcher search = getSearch();
// 范围查询
// true表示闭区间（是否包含开始字符和结束字符，默认为true）
Query query = new TermRangeQuery(field, start, end, true, true);
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
-----------------------------------------------------------------
lucene的搜索_其他常用Query搜索
-----------------------------------------------------------------
======前缀搜索（prefixquery）
Query query = new PrefixQuery(new Term(field, value));
======通配符搜索（wildcardquery）
Query query = new WildcardQuery(new Term(field, value));
//使用方法
sutil.SearchByWildCard("name", "l*", 3);
在传入的value中可以使用通配符? 和 *
？表示匹配一个字符，*表示匹配任意多个字符。可以在任何位置使用。
=======可以连接多个条件（BooleanQuery）
BooleanQuery query = new BooleanQuery();
// Occur.Must表必须
//Occur.SHOULD表示可有可无
//Occur.MUST_NOT表示必须没有
query.add(new TermQuery(new Term("name", "lili")), Occur.MUST);
query.add(new TermQuery(new Term("content", "hello")), Occur.MUST);
=======短语查询（phrasequery）
PhraseQuery query = new PhraseQuery();
// setSlop()设置跳数,及两个单词之间有几个单词
query.setSlop(1);
// 设置field字段，即哪两个单词
// 第一个term
query.add(new Term("content", "i"));
// 产生距离后的第二个term
query.add(new Term("content", "basketball"));
======模糊查询（FuzzyQuery）
//会匹配有一个字符出错的情况
Query query=new FuzzyQuery(new Term("name", "mirk"));
-------------------------------------------------------------
lucene的搜索_基于QueryParser的搜索
-------------------------------------------------------------
//基于字符串操作
public void SearchByQueryParse(Query query,int num){
try {
IndexSearcher search = getSearch();
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
//使用query查询(创建queryparser，再通过queryparser创建query)
// 1.创建Parse对象(设置默认搜索域为content)
QueryParser parse = new QueryParser(Version.LUCENE_35, "content",new StandardAnalyzer(Version.LUCENE_35));
// 改变空格的默认操作(改为AND型)
parse.setDefaultOperator(Operator.AND);
// 开启第一个字符的通配符匹配(*xxx,?xxx),默认关闭,因为效率比较低
parse.setAllowLeadingWildcard(true);
// 2.通过parse生成query(搜索content域中包含有like的)
Query query = parse.parse("like");
// 能够一直加条件(空格默认就是OR)
query = parse.parse("basketball i");
// 改变搜索域(域:值)
query = parse.parse("name:mark");
// 同样能进行*或？的通配符匹配(通配符默认不能放在首位)
query = parse.parse("name:*i");
// name中不包含mark,但是content中包含basketball(-和+必须放在域说明的前面)
query = parse.parse("- name:mark + basketball");
// id的1~3(TO表示一个闭区间,TO必须是大写的)
query = parse.parse("id:[1 TO 3]");
// {}表示1~3的开区间匹配
query = parse.parse("id:{1 TO 3}");
// name域值是lili或mark,默认域值是game
query = parse.parse("name:(lili OR mark) AND game");
// 两个‘’号表示短语匹配
query = parse.parse("'i like basketball'");
// 表示i basketball之间有一个单词遗漏的匹配
query = parse.parse(""i basketball"~1");
// 加个~就能模糊查询mark
query = parse.parse("name:mirk~");
// 没有办法匹配数字范围(自己扩展parse)
query = parse.parse("attach:[1 TO 3]");
sutil.SearchByQueryParse(query, 5);
------------------------------------------------------------
简单分页搜索
------------------------------------------------------------
Lucene通过再查询的方式：将所有数据取出，再进行分段分页
3.5以后使用的是searchAfter
//第一种分页方式（通过取出全部数据，再通过start和end对数据进行分页）
public void searchPage(String query,int pageIndex,int pageSize) {
try {
Directory dir = FileIndexUtils.getDirectory();
IndexSearcher searcher = getSearcher(dir);
QueryParser parser = new QueryParser(Version.LUCENE_35,"content",new StandardAnalyzer(Version.LUCENE_35));
Query q = parser.parse(query);
TopDocs tds = searcher.search(q, 500);
ScoreDoc[] sds = tds.scoreDocs;
int start = (pageIndex-1)*pageSize;
int end = pageIndex*pageSize;
for(int i=start;i<end;i++) {
Document doc = searcher.doc(sds[i].doc);
System.out.println(sds[i].doc+":"+doc.get("path")+"-->"+doc.get("filename"));
}
searcher.close();
} catch (org.apache.lucene.queryParser.ParseException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
-----------------------------------------------------------
lucene的搜索_基于searchAfter的实现（Lucene3.5之后）
-----------------------------------------------------------
/**
* 根据页码和分页大小获取上一次的最后一个ScoreDoc
*/
private ScoreDoc getLastScoreDoc(int pageIndex,int pageSize,Query query,IndexSearcher searcher) throws IOException {
if(pageIndex==1)return null;//如果是第一页就返回空
int num = pageSize*(pageIndex-1);//获取上一页的数量
//每次只取上面所有的元素
TopDocs tds = searcher.search(query, num);
return tds.scoreDocs[num-1];
}
public void searchPageByAfter(String query,int pageIndex,int pageSize) {
try {
Directory dir = FileIndexUtils.getDirectory();
IndexSearcher searcher = getSearcher(dir);
QueryParser parser = new QueryParser(Version.LUCENE_35,"content",new StandardAnalyzer(Version.LUCENE_35));
Query q = parser.parse(query);
//先获取上一页的最后一个元素
ScoreDoc lastSd = getLastScoreDoc(pageIndex, pageSize, q, searcher);
//通过最后一个元素搜索下页的pageSize个元素
TopDocs tds = searcher.searchAfter(lastSd,q, pageSize);
for(ScoreDoc sd:tds.scoreDocs) {
Document doc = searcher.doc(sd.doc);
System.out.println(sd.doc+":"+doc.get("path")+"-->"+doc.get("filename"));
}
searcher.close();
} catch (org.apache.lucene.queryParser.ParseException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
代码片段
package test.lucene.index;
import java.io.IOException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
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.CorruptIndexException;
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.BooleanQuery;
import org.apache.lucene.search.FuzzyQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.NumericRangeQuery;
import org.apache.lucene.search.PhraseQuery;
import org.apache.lucene.search.PrefixQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TermRangeFilter;
import org.apache.lucene.search.TermRangeQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.search.WildcardQuery;
import org.apache.lucene.search.BooleanClause.Occur;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;
public class SearchUtil {
/*
* 假设6个文档
*/
private String[] ids = { "1", "2", "3", "4", "5", "6" };
private String[] emails = { "[email protected]", "[email protected]", "[email protected]",
"[email protected]", "[email protected]", "[email protected]" };
private String[] contents = { "hello boy,i like pingpang", "like boy",
"xx bye i like swim", "hehe, i like basketball",
"dd fsfs, i like movie", "hello xxx,i like game" };
private int[] attachs = { 2, 3, 1, 4, 5, 5 };
private String[] names = { "lili", "wangwu", "lisi", "jack", "tom", "mark" };
// 设置加权map
private Map<String, Float> scores = new HashMap<String, Float>();
private Directory directory;
private IndexReader reader;
public SearchUtil() {
directory = new RAMDirectory();
}
/*
* 添加索引
*/
public void index() {
IndexWriter writer = null;
try {
writer = new IndexWriter(directory, new IndexWriterConfig(
Version.LUCENE_35, new StandardAnalyzer(Version.LUCENE_35)));
writer.deleteAll();
// 创建documents
Document document = null;
for (int i = 0; i < ids.length; i++) {
document = new Document();
document.add(new Field("id", ids[i], Field.Store.YES,
Field.Index.NOT_ANALYZED_NO_NORMS));
document.add(new Field("email", emails[i], Field.Store.YES,
Field.Index.NOT_ANALYZED)); // 不分词
document.add(new Field("content", contents[i], Field.Store.NO,
Field.Index.ANALYZED));
document.add(new Field("name", names[i], Field.Store.YES,
Field.Index.NOT_ANALYZED));
// 为数字添加索引
document.add(new NumericField("attach", Field.Store.YES, true)
.setIntValue(attachs[i]));
/*
* document.setBoost(float) 设置评级
*/
String et = emails[i].substring(emails[i].lastIndexOf("@") + 1);
// System.out.println(et);
if (scores.containsKey(et)) {
document.setBoost(scores.get(et));
} else {
document.setBoost(0.5f);
}
writer.addDocument(document);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (writer != null) {
try {
writer.close();
writer = null;
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/*
* 创建IndexSearch的方法
*/
public IndexSearcher getSearch() {
try {
if (reader == null) {
reader = IndexReader.open(directory);
} else {
IndexReader read = IndexReader.openIfChanged(reader);
if (read != null) {
reader.close();
reader = read;
}
}
return new IndexSearcher(reader);
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
// 精确匹配查询
public void SearchByTerm(String field, String name, int num) {
try {
IndexSearcher search = getSearch();
Query query = new TermQuery(new Term(field, name));
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// 基于字符串的范围的查询
public void SearchByTermRange(String field, String start, String end,
int num) {
try {
IndexSearcher search = getSearch();
// 范围查询
// true表示闭区间
Query query = new TermRangeQuery(field, start, end, true, true);
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// 基于数字的范围的查询
public void SearchByNumricRange(String field, int start, int end, int num) {
try {
IndexSearcher search = getSearch();
// 范围查询
// true表示闭区间
Query query = NumericRangeQuery.newIntRange(field, start, end,
true, true);
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// 前缀搜索
public void SearchByPrefix(String field, String value, int num) {
try {
IndexSearcher search = getSearch();
Query query = new PrefixQuery(new Term(field, value));
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// 通配符搜索
public void SearchByWildCard(String field, String value, int num) {
try {
IndexSearcher search = getSearch();
Query query = new WildcardQuery(new Term(field, value));
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// 多个条件搜索
public void SearchByBoolean(int num) {
try {
IndexSearcher search = getSearch();
BooleanQuery query = new BooleanQuery();
// Occur.Must表必须 Occur.SHOULD表示可有可无 Occur.MUST_NOT表示必须没有
query.add(new TermQuery(new Term("name", "lili")), Occur.MUST);
query.add(new TermQuery(new Term("content", "hello")), Occur.MUST);
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// 短语查询
public void SearchByPhrase(int num) {
try {
IndexSearcher search = getSearch();
PhraseQuery query = new PhraseQuery();
// setSlop()设置跳数,及两个单词之间有几个单词
query.setSlop(1);
// 设置field字段，即哪两个单词
query.add(new Term("content", "i"));
query.add(new Term("content", "basketball"));
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// 模糊查询
public void SearchByFuzzy(int num) {
try {
IndexSearcher search = getSearch();
Query query=new FuzzyQuery(new Term("name", "mirk"));
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
//基于字符串操作
public void SearchByQueryParse(Query query,int num){
try {
IndexSearcher search = getSearch();
TopDocs tds = search.search(query, num);
System.out.println("一共查询了：" + tds.totalHits);
for (ScoreDoc sdc : tds.scoreDocs) {
Document doc = search.doc(sdc.doc);
System.out.println(sdc.doc + doc.get("name") + "["
+ doc.get("email") + "," + doc.get("id") + ","
+ doc.get("attach") + "]");
}
search.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
package test.lucene.index;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.queryParser.QueryParser.Operator;
import org.apache.lucene.search.Query;
import org.apache.lucene.util.Version;
import org.junit.Before;
import org.junit.Test;
public class SearchTest {
private SearchUtil sutil;
@Before
public void init() throws Exception {
sutil = new SearchUtil();
}
@Test
public void searchByterm() {
sutil.index();
sutil.SearchByTerm("name", "mark", 3);
}
@Test
public void searchByRangeTerm() {
sutil.index();
sutil.SearchByTermRange("id", "1", "3", 10);
// 查询name以a开头和s结尾的
sutil.SearchByTermRange("name", "a", "s", 10);
// 由于attach是数字类型，使用termrange无法查询
sutil.SearchByTermRange("attach", "1", "5", 10);
}
@Test
public void searchByNumricRange() {
sutil.index();
// 由于attach是数字类型，使用NumricRange进行查询
sutil.SearchByNumricRange("attach", 2, 5, 10);
}
@Test
public void searchByPrefix() {
sutil.index();
// 前缀搜索
sutil.SearchByPrefix("name", "l", 3);
}
@Test
public void searchByWildCard() {
sutil.index();
// 通配符搜索
sutil.SearchByWildCard("name", "l*", 3);
}
@Test
public void searchByBoolean() {
sutil.index();
// 多条件查询
sutil.SearchByBoolean(3);
}
@Test
public void searchByPhrase() {
sutil.index();
// 短语查询
sutil.SearchByPhrase(5);
}
@Test
public void searchByFuzzy() {
sutil.index();
// 模糊查询
sutil.SearchByFuzzy(5);
}
@Test
public void searchByqueryParse() throws Exception {
sutil.index();
// 1.创建Parse对象(设置默认搜索域为content)
QueryParser parse = new QueryParser(Version.LUCENE_35, "content",
new StandardAnalyzer(Version.LUCENE_35));
// 改变空格的默认操作(改为AND型)
parse.setDefaultOperator(Operator.AND);
// 开启第一个字符的通配符匹配(*xxx,?xxx),默认关闭,因为效率比较低
parse.setAllowLeadingWildcard(true);
// 2.通过parse生成query(搜索content域中包含有like的)
Query query = parse.parse("like");
// 能够一直加条件(空格默认就是OR)
query = parse.parse("basketball i");
// 改变搜索域(域:值)
query = parse.parse("name:mark");
// 同样能进行*或？的通配符匹配(通配符默认不能放在首位)
query = parse.parse("name:*i");
// name中不包含mark,但是content中包含basketball(-和+必须放在域说明的前面)
query = parse.parse("- name:mark + basketball");
// id的1~3(TO表示一个闭区间,TO必须是大写的)
query = parse.parse("id:[1 TO 3]");
// {}表示1~3的开区间匹配
query = parse.parse("id:{1 TO 3}");
// name域值是lili或mark,默认域值是game
query = parse.parse("name:(lili OR mark) AND game");
// 两个‘’号表示短语匹配
query = parse.parse("'i like basketball'");
// 表示i basketball之间有一个单词遗漏的匹配
query = parse.parse(""i basketball"~1");
// 加个~就能模糊查询mark
query = parse.parse("name:mirk~");
// 没有办法匹配数字范围(自己扩展parse)
query = parse.parse("attach:[1 TO 3]");
sutil.SearchByQueryParse(query, 5);
}
}