Lucene wild card search - search

Question

How can I perform a wildcard search in Lucene ?
I have the text: "1997_titanic"
If I search like "1997_titanic", it is returning a result, but I am not able to do below two searches:
1) If I search with only 1997 it is not returning any results.
2) Also if there is a space, such as in "spider man", that is not finding any results.
I retrieve all movie information from a DB and store it in Lucene Documents:
public Document createMovieDoc(Movie m){
document.add(new StoredField("moviename", m.getName()));
TextField field = new TextField("movienameSearch", m.getName().toLowerCase(), Store.NO);
field.setBoost(5.0f);
document.add(field);
}
And to search, I have this method:
public List searh(String txt){
PhraseQuery phQuery= new PhraseQuery();
Term term = new Term("movienameSearch", txt.toLowerCase());
BooleanQuery b = new BooleanQuery();
b.add(phQuery, Occur.SHOULD);
TopFieldDocs tp= searcher.search(b, 20, ..);
for(int i=0;i<tp.length;i++)
{
int mId = tp[i].doc;
Document d = searcher.doc(mId);
String moviename = d.get("moviename");
list.add(moviename);
}
return list;
}

Answer 1

I'm not sure what analyzer you are using to index. Sounds like maybe WhitespaceAnalyzer? It sounds like, when indexing "1997_titanic" remains a single token, while "spider man" is split into the token "spider" and "man".
Could also be SimpleAnalyzer which uses a LetterTokenizer. This would make it impossible to search for "1997", since that tokenizer will eliminate all numbers for the indexed representation of the text.
Your search method doesn't look right. You aren't adding any terms to your PhraseQuery, so I wouldn't expect it to find anything. You must add some terms in order for anything to be found. You create a Term in what you've provided, but nothing is ever done with that Term. Maybe this has something to do with how you've pick your excerpts, or something? Not sure, I'm a bit confused by that.
In order to manually construct a PhraseQuery you must add each term individually, so to search for "spider man", you would do something like:
PhraseQuery phQuery= new PhraseQuery();
phQuery.add(new Term("movienameSearch", "spider"));
phQuery.add(new Term("movienameSearch", "man"));
This requires you to know what the analyzer was doing at index time, and tokenize the input yourself to suit. The simpler solution is to just use the QueryParser:
//With whatever analyzer you like to use.
QueryParser parser = new QueryParser(Version.LUCENE_46, "defaultField", analyzer);
Query query = parser.parse("movienameSearch:\"" + txt.toLowerCase() + "\"");
TopFieldDocs tp= searcher.search(query, 20);
This allows you to rely on the same analyzer to index and query, so you don't have to know how to tokenize your phrases to suit.
As far as finding "1997" and "titanic" individually, I would recommend just using StandardAnalyzer. It will tokenize those into discrete tokens, allowing them to be searched very easily, with a simple query like: movienameSearch:1997.