Am using Lucene API in a .net web application. I want to use the same instance of Indexsearcher for all the requests.Hence am storing indexsearcher instance in http cache.<
I also have a web application that uses the Lucene API to query (my web app does not writes on the index) and I create a new instance of the searcher for every request. It might not be very "performant" but I never had that kind of problem.
If you'd like, my web app is on Google Code so you can download the source code and take a look at what I did. Here's the url to the project http://code.google.com/p/goomez/