How to perform a wildcard search in Lucene

Question

I know that Lucene has extensive support for wildcard searches and I know you can search for things like:

Stackover* (which will return Stackoverflow)

That said, my users aren't interested in learning a query syntax. Can Lucene perform this type of wildcard search using an out-of-box Analyzer? Or should I append "*" to every search query?

Answer 1

Doing this with string manipulations is tricky to get right, especially since the QueryParser supports boosting, phrases, etc.

You could use a QueryVisitor that rewrites TermQuery into PrefixQuery.

public class PrefixRewriter : QueryVisitor {
    protected override Query VisitTermQuery(TermQuery query) {
        var term = query.GetTerm();
        var newQuery = new PrefixQuery(term);
        return CopyBoost(query, newQuery);
    }
}

The QueryVisitor base class can currently be found at gitlab.

The code was initially posted on a blog post which is now defunct. The blog post is still available at archive.org.