Lucene index which tier?

while describing a system havi开发者_JAVA百科ng a three tier architecture, which tier would Lucene come under-the Business Logic or the Data Tier?

If you are using Lucene, then you are not really three-tier. So the answer rather depends on whether you are after clear and accurate description of how your software is structured, or merely have some commercial/political reason to claim buzzword compliance.

If the latter, then you probably won't really be provably wrong if you say it is in either the data or application tiers. But you might be better off adopting a new, and hopefully less-inaccurate, one:

http://www.webopedia.com/quick_ref/app.arch.asp