Different behaviour of JapaneseAnalyzer at indexing time vs. at search time results in no matches for some words. [LUCENE-5905]
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Description
A document with the word 秋葉原 in the body, when analysed by the JapaneseAnalyzer (AKA Kuromoji), cannot be found when searching for the same text as a phrase query.
Two programs are provided to reproduce the issue. Both programs print out the term docs and positions and then the result of parsing the phrase query.
As shown by the output, at analysis time, there is a lone Japanese term "秋葉原". At query parsing time, there are **three** such terms - "秋葉" and "秋葉原" at position 0 and "原" at position 1. Because all terms must be present for a phrase query to be a match, the query never matches, which is quite a serious issue for us.
**Any workarounds, no matter how hacky, would be extremely helpful at this point.**
My guess is that this is a quirk with the analyser. If it happened with StandardAnalyzer, surely someone would have discovered it before I did.
Lucene 5.2.1 reproduction:
```java
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.ja.JapaneseAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
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.LeafReader;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.MultiFields;
import org.apache.lucene.index.PostingsEnum;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.queryparser.flexible.standard.StandardQueryParser;
import org.apache.lucene.queryparser.flexible.standard.config.StandardQueryConfigHandler;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
public class LuceneMissingTerms {
public static void main(String[] args) throws Exception {
try (Directory directory = new RAMDirectory()) {
Analyzer analyser = new JapaneseAnalyzer();
try (IndexWriter writer = new IndexWriter(directory, new IndexWriterConfig(analyser))) {
Document document = new Document();
document.add(new TextField("content", "blah blah commercial blah blah \u79CB\u8449\u539F blah blah", Field.Store.NO));
writer.addDocument(document);
}
try (IndexReader multiReader = DirectoryReader.open(directory)) {
for (LeafReaderContext leaf : multiReader.leaves()) {
LeafReader reader = leaf.reader();
Terms terms = MultiFields.getFields(reader).terms("content");
TermsEnum termsEnum = terms.iterator();
BytesRef text;
//noinspection NestedAssignment
while ((text = termsEnum.next()) != null) {
System.out.println("term: " + text.utf8ToString());
Bits liveDocs = reader.getLiveDocs();
PostingsEnum postingsEnum = termsEnum.postings(liveDocs, null, PostingsEnum.POSITIONS);
int doc;
//noinspection NestedAssignment
while ((doc = postingsEnum.nextDoc()) != DocIdSetIterator.NO_MORE_DOCS) {
System.out.println(" doc: " + doc);
int freq = postingsEnum.freq();
for (int i = 0; i < freq; i++) {
int pos = postingsEnum.nextPosition();
System.out.println(" pos: " + pos);
}
}
}
}
StandardQueryParser queryParser = new StandardQueryParser(analyser);
queryParser.setDefaultOperator(StandardQueryConfigHandler.Operator.AND);
// quoted to work around strange behaviour of StandardQueryParser treating this as a boolean query.
Query query = queryParser.parse("\"\u79CB\u8449\u539F\"", "content");
System.out.println(query);
TopDocs topDocs = new IndexSearcher(multiReader).search(query, 10);
System.out.println(topDocs.totalHits);
}
}
}
}
```
Lucene 4.9 reproduction:
```java
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.ja.JapaneseAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.AtomicReader;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.DocsAndPositionsEnum;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.MultiFields;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.queryparser.flexible.standard.StandardQueryParser;
import org.apache.lucene.queryparser.flexible.standard.config.StandardQueryConfigHandler;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.Version;
public class LuceneMissingTerms {
public static void main(String[] args) throws Exception {
try (Directory directory = new RAMDirectory()) {
Analyzer analyser = new JapaneseAnalyzer(Version.LUCENE_4_9);
try (IndexWriter writer = new IndexWriter(directory,
new IndexWriterConfig(Version.LUCENE_4_9, analyser))) {
Document document = new Document();
document.add(new TextField("content", "blah blah
commercial blah blah \u79CB\u8449\u539F blah blah", Field.Store.NO));
writer.addDocument(document);
}
try (IndexReader multiReader =
DirectoryReader.open(directory)) {
for (AtomicReaderContext atomicReaderContext :
multiReader.leaves()) {
AtomicReader reader = atomicReaderContext.reader();
Terms terms =
MultiFields.getFields(reader).terms("content");
TermsEnum termsEnum = terms.iterator(null);
BytesRef text;
//noinspection NestedAssignment
while ((text = termsEnum.next()) != null) {
System.out.println("term: " + text.utf8ToString());
Bits liveDocs = reader.getLiveDocs();
DocsAndPositionsEnum docsAndPositionsEnum
= termsEnum.docsAndPositions(liveDocs, null);
int doc;
//noinspection NestedAssignment
while ((doc =
docsAndPositionsEnum.nextDoc()) != DocIdSetIterator.NO_MORE_DOCS) {
System.out.println(" doc: " + doc);
int freq = docsAndPositionsEnum.freq();
for (int i = 0; i < freq; i++) {
int pos =
docsAndPositionsEnum.nextPosition();
System.out.println(" pos: " + pos);
}
}
}
}
StandardQueryParser queryParser = new
StandardQueryParser(analyser);
queryParser.setDefaultOperator(StandardQueryConfigHandler.Operator.AND);
// quoted to work around strange behaviour of
StandardQueryParser treating this as a boolean query.
Query query =
queryParser.parse("\"\u79CB\u8449\u539F\"", "content");
System.out.println(query);
TopDocs topDocs = new
IndexSearcher(multiReader).search(query, 10);
System.out.println(topDocs.totalHits);
}
}
}
}
```
Lucene 3.6.2 reproduction:
```java
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.ja.JapaneseAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
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.index.TermEnum;
import org.apache.lucene.index.TermPositions;
import org.apache.lucene.queryParser.standard.StandardQueryParser;
import org.apache.lucene.queryParser.standard.config.StandardQueryConfigHandler;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;
import org.junit.Test;
import static org.hamcrest.Matchers.*;
import static org.junit.Assert.*;
public class TestJapaneseAnalysis {
`@Test`
public void testJapaneseAnalysis() throws Exception {
try (Directory directory = new RAMDirectory()) {
Analyzer analyser = new JapaneseAnalyzer(Version.LUCENE_36);
try (IndexWriter writer = new IndexWriter(directory,
new IndexWriterConfig(Version.LUCENE_36, analyser))) {
Document document = new Document();
document.add(new Field("content", "blah blah
commercial blah blah \u79CB\u8449\u539F blah blah", Field.Store.NO,
Field.Index.ANALYZED));
writer.addDocument(document);
}
try (IndexReader reader = IndexReader.open(directory);
TermEnum terms = reader.terms(new Term("content", ""));
TermPositions termPositions = reader.termPositions()) {
do {
Term term = terms.term();
if (term.field() != "content") {
break;
}
System.out.println(term);
termPositions.seek(terms);
while (termPositions.next()) {
System.out.println(" " + termPositions.doc());
int freq = termPositions.freq();
for (int i = 0; i < freq; i++) {
System.out.println(" " +
termPositions.nextPosition());
}
}
}
while (terms.next());
StandardQueryParser queryParser = new
StandardQueryParser(analyser);
queryParser.setDefaultOperator(StandardQueryConfigHandler.Operator.AND);
// quoted to work around strange behaviour of
StandardQueryParser treating this as a boolean query.
Query query =
queryParser.parse("\"\u79CB\u8449\u539F\"", "content");
System.out.println(query);
TopDocs topDocs = new
IndexSearcher(reader).search(query, 10);
assertThat(topDocs.totalHits, is(1));
}
}
}
}
```
---
Migrated from [LUCENE-5905](https://issues.apache.org/jira/browse/LUCENE-5905) by Trejkaz, 1 vote, updated Nov 01 2017
Environment:
```
Java 8u5
```
Contributor guide
Research direction
Start by running the Java reproductions in the issue with JapaneseAnalyzer and StandardQueryParser, comparing the terms and positions produced during indexing and phrase-query parsing. Done means the reproduced 秋葉原 phrase query matches the indexed document without requiring a workaround.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- java
- Domain
- search
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100