Mailing List Archive

Hi,

I am using Apache Lucene 8.5.0 version



I have written a simple program to create index of words with special
character.



Example I have indexed the word *temp/hello*



Now I want to search the word with wildcard query *te*/hello*



I get the error* : *Exception in thread "main"
*org.apache.lucene.queryparser.classic.ParseException*: Cannot parse
'te*/hello': Lexical error at line 1, column 10. Encountered: <EOF> after
: "/hello"



When I escape the query with QueryParser.escape method it doesn’t yield any
results when special characters are part of query



*Can someone suggest the right way for indexing and searching words with
special characters?*



Here’s my simple program



*import* java.io.BufferedReader;

*import* java.io.IOException;

*import* java.io.InputStreamReader;

*import* java.nio.file.Paths;



*import* org.apache.lucene.analysis.Analyzer;

*import* org.apache.lucene.analysis.custom.CustomAnalyzer;

*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.DirectoryReader;

*import* org.apache.lucene.index.IndexReader;

*import* org.apache.lucene.index.IndexWriter;

*import* org.apache.lucene.index.IndexWriterConfig;

*import* org.apache.lucene.index.IndexWriterConfig.OpenMode;

*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.Query;

*import* org.apache.lucene.search.ScoreDoc;

*import* org.apache.lucene.search.TopDocs;

*import* org.apache.lucene.store.Directory;

*import* org.apache.lucene.store.MMapDirectory;



*public* *class* HelloLucene {

*private* *static* Analyzer buildAnalyzer() *throws* IOException {

*return* CustomAnalyzer.*builder*()

.withTokenizer("keyWord")

.addTokenFilter("lowercase")

.build();



}





*public* *static* *void* main(String[] args) *throws* IOException,
ParseException {

Analyzer analyzer = *buildAnalyzer*();

// 1. create the index

Directory index = *new* MMapDirectory(Paths.*get*("c:\\temp\\index"
));



IndexWriterConfig config = *new* IndexWriterConfig(analyzer);



String indexType = "create";

*if* ("create".equals(indexType)) {

config.setOpenMode(OpenMode.*CREATE*);

} *else* {

config.setOpenMode(OpenMode.*CREATE_OR_APPEND*);

}

IndexWriter w = *new* IndexWriter(index, config);





*long* start = System.*currentTimeMillis*();

*addDoc*(w, "Temp/Hello", "Artifact");



*long* end = System.*currentTimeMillis*();

w.close();



*for* (*int* i = 0; i < 100; i++) {



// 2. query

BufferedReader input = *new* BufferedReader(*new*
InputStreamReader(System.*in*));

String query = input.readLine();



//Prefix Search



QueryParser queryParser = *new* QueryParser("Name",analyzer);

queryParser.setAllowLeadingWildcard(*true*);

Query q = queryParser.parse(QueryParser.*escape*(query));





// 3. search



*int* hitsPerPage = 10;

IndexReader reader = DirectoryReader.*open*(index);

IndexSearcher searcher = *new* IndexSearcher(reader);

TopDocs docs = searcher.search(q, hitsPerPage);

ScoreDoc[] hits = docs.scoreDocs;



// 4. display results

*System.**out*.println("Found " + hits.length + " hits.");

*for* (*int* j = 0; j < hits.length; ++j) {

*int* docId = hits[j].doc;

Document d = searcher.doc(docId);

*System.**out*.println((j + 1) + ". " + d.get("Name") + "\t"
+ d.get("Type"));

}



reader.close();

}



}



*private* *static* *void* addDoc(IndexWriter w, String name, String type)
*throws* IOException {

Document doc = *new* Document();

doc.add(*new* TextField("Name", name, Field.Store.*YES*));



// use a string field for *isbn* because we don't want it
*tokenized*

doc.add(*new* TextField("Type", type, Field.Store.*YES*));

w.addDocument(doc);

}

}