Lucene - TermRangeQuery

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TermRangeQuery class is used when a range of textual terms are to be searched.

Class Declaration

Following is the declaration for org.apache.lucene.search.TermRangeQuery class −

public class TermRangeQuery
   extends AutomatonQuery

Class Constructors

S.No.	Constructor & Description
1	TermRangeQuery(String field, BytesRef lowerTerm, BytesRef upperTerm, boolean includeLower, boolean includeUpper) Constructs a query selecting all terms greater/equal than lowerTerm but less/equal than upperTerm.
2	TermRangeQuery(String field, BytesRef lowerTerm, BytesRef upperTerm, boolean includeLower, boolean includeUpper, MultiTermQuery.RewriteMethod rewriteMethod) Constructs a query selecting all terms greater/equal than lowerTerm but less/equal than upperTerm.

Class Methods

S.No.	Method & Description
1	boolean equals(Object obj) Override and implement query instance equivalence properly in a subclass.
2	BytesRef getLowerTerm() Returns the lower value of this range query.
3	BytesRef getUpperTerm() Returns the upper value of this range query.
4	int hashCode() Override and implement query hash code properly in a subclass.
5	boolean includesLower() Returns true if the lower endpoint is inclusive.
6	boolean includesUpper() Returns true if the upper endpoint is inclusive.
7	static TermRangeQuery newStringRange(String field, String lowerTerm, String upperTerm, boolean includeLower, boolean includeUpper) Factory that creates a new TermRangeQuery using Strings for term text.
8	static TermRangeQuery newStringRange(String field, String lowerTerm, String upperTerm, boolean includeLower, boolean includeUpper, MultiTermQuery.RewriteMethod rewriteMethod) Factory that creates a new TermRangeQuery using Strings for term text.
9	static Automaton toAutomaton(BytesRef lowerTerm, BytesRef upperTerm, boolean includeLower, boolean includeUpper)
10	String toString(String field) Prints a user-readable version of this query.

Methods Inherited

This class inherits methods from the following classes −

• org.apache.lucene.search.AutomatonQuery
• org.apache.lucene.search.MultiTermQuery
• org.apache.lucene.search.Query
• java.lang.Object

Usage of TermRangeQuery

private void searchUsingTermRangeQuery(String searchQueryMin,
   String searchQueryMax)throws IOException, ParseException {
   searcher = new Searcher(indexDir);
   long startTime = System.currentTimeMillis();

   //create the term query object
   Query query = TermRangeQuery.newStringRange(LuceneConstants.FILE_NAME, 
   searchQueryMin,searchQueryMax,true,false);
   //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.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
   }
}

Example Application

To test search using TermRangeQuery, let us create a test Lucene application.

LuceneConstants.java

This class is used to provide various constants to be used across the sample application.

package com.tutorialspoint.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

This class is used to read the indexes made on raw data and searches data using the Lucene library.

package com.tutorialspoint.lucene;

import java.io.IOException;
import java.nio.file.Paths;
import java.text.ParseException;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.index.DirectoryReader;
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;
import org.apache.lucene.util.QueryBuilder;

public class Searcher {

   IndexSearcher indexSearcher;
   QueryBuilder queryBuilder;
   Query query;

   public Searcher(String indexDirectoryPath) 
      throws IOException {
      DirectoryReader indexDirectory = DirectoryReader.open(FSDirectory.open(Paths.get(indexDirectoryPath)));
      indexSearcher = new IndexSearcher(indexDirectory);
      StandardAnalyzer analyzer = new StandardAnalyzer();
      queryBuilder = new QueryBuilder(analyzer);
   }

   public TopDocs search( String searchQuery) 
      throws IOException, ParseException {
      query = queryBuilder.createPhraseQuery(LuceneConstants.CONTENTS, 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.storedFields().document(scoreDoc.doc);	
   }
}

LuceneTester.java

This class is used to test the searching capability of the Lucene library.

package com.tutorialspoint.lucene;

import java.io.IOException;
import java.text.ParseException;

import org.apache.lucene.document.Document;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermRangeQuery;
import org.apache.lucene.search.TopDocs;

public class LuceneTester {
	
   String indexDir = "D:\\Lucene\\Index";
   String dataDir = "D:\\Lucene\\Data";
   Searcher searcher;

   public static void main(String[] args) {
      LuceneTester tester;
      try {
         tester = new LuceneTester();
         tester.searchUsingTermRangeQuery("record2.txt","record6.txt");
      } catch (IOException e) {
         e.printStackTrace();
      } catch (ParseException e) {
         e.printStackTrace();
      }
   }

   private void searchUsingTermRangeQuery(String searchQueryMin,
      String searchQueryMax)throws IOException, ParseException {
      searcher = new Searcher(indexDir);
      long startTime = System.currentTimeMillis();

      //create the term query object
      Query query = TermRangeQuery.newStringRange(LuceneConstants.FILE_NAME, 
      searchQueryMin,searchQueryMax,true,false);
      //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.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
      }
   }
}

Data & Index Directory Creation

I've used 10 text files from record1.txt to record10.txt containing names and other details of the students and put them in the directory D:\Lucene\Data. Test Data. An index directory path should be created as D:\Lucene\Index. After running the indexing program in the chapter Lucene - Indexing Process, you can see the list of index files created in that folder.

Running the Program

Once you are done with the creation of the source, the raw data, the data directory, the index directory and the indexes, you can proceed by compiling and running your program. To do this, keep the LuceneTester.Java file tab active and use either the Run option available in the Eclipse IDE or use Ctrl + F11 to compile and run your LuceneTester application. If your application runs successfully, it will print the following message in Eclipse IDE's console −

Output

4 hits documents found. Time :75ms
File: D:\lucene\Data\record2.txt
File: D:\lucene\Data\record3.txt
File: D:\lucene\Data\record4.txt
File: D:\lucene\Data\record5.txt