MatchAllDocsQuery
MatchAllDocsQuery顾名思义,匹配所有文档。
Class 声明 (Class Declaration)
以下是org.apache.lucene.search.MatchAllDocsQuery类的声明:
public class MatchAllDocsQuery
extends Query
类构造函数 (Class Constructors)
S.No. | 构造函数和描述 |
---|---|
1 | MatchAllDocsQuery() |
2 | MatchAllDocsQuery(String normsField) |
Class Methods
S.No. | 方法和描述 |
---|---|
1 | Weight create Weight(Searcher searcher) 专家:为此查询构造适当的权重实现。 |
2 | boolean equals(Object o) |
3 | void extractTerms(Set terms) void extractTerms(Set terms) 专家:将此查询中出现的所有术语添加到术语集中。 |
4 | int hashCode() |
5 | String to String(String field) 将查询打印到字符串,假定字段为默认字段并省略。 |
方法继承 (Methods Inherited)
该类继承以下类中的方法 -
- org.apache.lucene.search.Query
- java.lang.Object
用法 (Usage)
private void searchUsingMatchAllDocsQuery(String searchQuery)
throws IOException, ParseException {
searcher = new Searcher(indexDir);
long startTime = System.currentTimeMillis();
//create the term query object
Query query = new MatchAllDocsQuery(searchQuery);
//do the search
TopDocs hits = searcher.search(query);
long endTime = System.currentTimeMillis();
System.out.println(hits.totalHits +
" documents found. Time :" + (endTime - startTime) + "ms");
for(ScoreDoc scoreDoc : hits.scoreDocs) {
Document doc = searcher.getDocument(scoreDoc);
System.out.print("Score: "+ scoreDoc.score + " ");
System.out.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
}
searcher.close();
}
例子 Example Application
让我们创建一个测试Lucene应用程序来使用MatchAllDocsQuery测试搜索。
步 | 描述 |
---|---|
1 | 在LuceneFirstApplication下创建一个名为LuceneFirstApplication的项目,如Lucene - First Application一章中所述。 您还可以使用Lucene - First Application创建的项目Lucene - First Application本章的Lucene - First Application章节来了解搜索过程。 |
2 | 按照Lucene - First Application章节中的说明创建LuceneConstants.java和Searcher.java 。 保持其余文件不变。 |
3 | 创建LuceneTester.java ,如下所述。 |
4 | 清理并构建应用程序以确保业务逻辑按照要求运行。 |
LuceneConstants.java
此类用于提供跨示例应用程序使用的各种常量。
package cn.xnip.lucene;
public class LuceneConstants {
public static final String CONTENTS = "contents";
public static final String FILE_NAME = "filename";
public static final String FILE_PATH = "filepath";
public static final int MAX_SEARCH = 10;
}
Searcher.java
此类用于读取对原始数据所做的索引,并使用Lucene库搜索数据。
package cn.xnip.lucene;
import java.io.File;
import java.io.IOException;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.queryParser.ParseException;
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.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;
public class Searcher {
IndexSearcher indexSearcher;
QueryParser queryParser;
Query query;
public Searcher(String indexDirectoryPath) throws IOException {
Directory indexDirectory =
FSDirectory.open(new File(indexDirectoryPath));
indexSearcher = new IndexSearcher(indexDirectory);
queryParser = new QueryParser(Version.LUCENE_36,
LuceneConstants.CONTENTS,
new StandardAnalyzer(Version.LUCENE_36));
}
public TopDocs search( String searchQuery)
throws IOException, ParseException {
query = queryParser.parse(searchQuery);
return indexSearcher.search(query, LuceneConstants.MAX_SEARCH);
}
public TopDocs search(Query query) throws IOException, ParseException {
return indexSearcher.search(query, LuceneConstants.MAX_SEARCH);
}
public Document getDocument(ScoreDoc scoreDoc)
throws CorruptIndexException, IOException {
return indexSearcher.doc(scoreDoc.doc);
}
public void close() throws IOException {
indexSearcher.close();
}
}
LuceneTester.java
该类用于测试Lucene库的搜索功能。
package cn.xnip.lucene;
import java.io.IOException;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.Term;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
public class LuceneTester {
String indexDir = "E:\\Lucene\\Index";
String dataDir = "E:\\Lucene\\Data";
Searcher searcher;
public static void main(String[] args) {
LuceneTester tester;
try {
tester = new LuceneTester();
tester.searchUsingMatchAllDocsQuery("");
} catch (IOException e) {
e.printStackTrace();
} catch (ParseException e) {
e.printStackTrace();
}
}
private void searchUsingMatchAllDocsQuery(String searchQuery)
throws IOException, ParseException {
searcher = new Searcher(indexDir);
long startTime = System.currentTimeMillis();
//create the term query object
Query query = new MatchAllDocsQuery(searchQuery);
//do the search
TopDocs hits = searcher.search(query);
long endTime = System.currentTimeMillis();
System.out.println(hits.totalHits +
" documents found. Time :" + (endTime - startTime) + "ms");
for(ScoreDoc scoreDoc : hits.scoreDocs) {
Document doc = searcher.getDocument(scoreDoc);
System.out.print("Score: "+ scoreDoc.score + " ");
System.out.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
}
searcher.close();
}
}
数据和索引目录创建
我使用了record1.txt中的10个文本文件到包含学生名字和其他详细信息的record10.txt,并将它们放在目录E:\Lucene\Data.。 索引目录路径应创建为E:\Lucene\Index 。 在Lucene - Indexing Process一章中运行索引程序后,您可以看到在该文件夹中创建的索引文件列表。
运行程序 (Running the Program)
完成源,原始数据,数据目录,索引目录和索引的创建后,可以继续编译和运行程序。 为此,请保持LuceneTester.Java文件选项卡处于活动状态,并使用Eclipse IDE中提供的Run选项或使用Ctrl + F11编译并运行LuceneTester应用程序。 如果您的应用程序成功运行,它将在Eclipse IDE的控制台中打印以下消息 -
10 documents found. Time :9ms
Score: 1.0 File: E:\Lucene\Data\record1.txt
Score: 1.0 File: E:\Lucene\Data\record10.txt
Score: 1.0 File: E:\Lucene\Data\record2.txt
Score: 1.0 File: E:\Lucene\Data\record3.txt
Score: 1.0 File: E:\Lucene\Data\record4.txt
Score: 1.0 File: E:\Lucene\Data\record5.txt
Score: 1.0 File: E:\Lucene\Data\record6.txt
Score: 1.0 File: E:\Lucene\Data\record7.txt
Score: 1.0 File: E:\Lucene\Data\record8.txt
Score: 1.0 File: E:\Lucene\Data\record9.txt