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36

answers:

1

Hi All,

I am trying to understand Lucene SpanNearQuery and wrote up a dummy example. I am looking for "not" followed by "fox" within 5 of each other. I would expect document 3 to be returned as the only hit. However, I end up getting no hits. Any thoughts on what might I be doing wrong will be appreciated.

Here is the code:

//indexing

public void doSpanIndexing()  throws IOException {   

IndexWriter writer=new IndexWriter(directory, AnalyzerUtil.getPorterStemmerAnalyzer(new StandardAnalyzer(Version.LUCENE_30)),IndexWriter.MaxFieldLength.LIMITED);

 Document doc1=new Document();
 doc1.add(new Field("content", " brown fox jumped ", Field.Store.YES, Index.ANALYZED,  Field.TermVector.WITH_POSITIONS_OFFSETS));
 writer.addDocument(doc1);


 Document doc2=new Document();
 doc2.add(new Field("content", "foxes not jumped over the huge fence", Field.Store.YES, Index.ANALYZED,Field.TermVector.WITH_POSITIONS_OFFSETS));
 writer.addDocument(doc2);

 Document doc3=new Document();
 doc3.add(new Field("content", " brown not fox", Field.Store.YES, Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS));
 writer.addDocument(doc3);


}

//searching
public void doSpanSearching(String text) throws CorruptIndexException, IOException, ParseException {

 IndexSearcher searcher=new IndexSearcher(directory);

 SpanTermQuery term1 = new SpanTermQuery(new Term("content", "not"));
 SpanTermQuery term2 = new SpanTermQuery(new Term("content", text));
 SpanNearQuery query = new SpanNearQuery(new SpanQuery[] {term1, term2}, 5, true);
 TopDocs topDocs=searcher.search(query,5);

for(int i=0; i<topDocs.totalHits; i++) {
   System.out.println("Hit Document number: "+topDocs.scoreDocs[i].doc);
   System.out.println("Hit Document score: "+topDocs.scoreDocs[i].score);
   Document result=searcher.doc(topDocs.scoreDocs[i].doc);
   System.out.println("Search result "+(i+1)+ " is "+result.get("content"));

  }

}
A: 

"Not" is a stop word in the standard analyzer (i.e. it is removed from your text). Can you try it with another word which is not a stop word?

Xodarap
I substituted "not" with "brown", still no results. Any ideas? Thanks for the pointer on "Not" being omitted during indexing. I completely overlooked it.
cer_albastru