The Lucene search engine: Powerful, flexible, and free

The Lucene search engine: Powerful, flexible, and free: "Summary
Lucene is a Java-based open source toolkit for text indexing and searching. It is easy to use, flexible, and powerful -- a model of good object-oriented software architecture. Powerful abstractions and useful concrete implementations make Lucene very flexible, and allow new users to get up and running quickly and painlessly. In this article, we explore what Lucene does, how it works, and what software engineers can learn from its design. (3,400 words)"