Apache Lucene is a high-performance, cross-platform, full-featured Information Retrieval library in open source, suitable for nearly every application that requires full-text search features.

Since its introduction nearly 10 years ago, Apache Lucene has become a competitive player for developing extensible, high-performance full-text search solutions. The experience accumulated over time by the community of Lucene committers and contributors and the innovations they have engineered have delivered significant ongoing advances in Lucene’s capabilities.

This white paper describes the new features and improvements in the latest versions, Apache Lucene 2.9 and 3.0. It is intended mainly for programmers familiar with the broad base of Lucene’s capabilities, though those new to Lucene should also find it a useful exploration of the newest features. Key topics such as how to upgrade from 2.9 to 3.0, as well as considerations for migrating from Lucene to Solr, are also addressed.

The release of version 2.9 makes Apache Lucene is now faster and more flexible than before. Learn about these new features and improvements:

• Near-real-time search
• Flexible indexing and segments
• High-performance numerical range queries
• New APIs introduced
• Critical bug fixes
• migrating from earlier versions to Lucene 2.9 or better

In the simplest terms, Lucene is now faster and more flexible than before. Historic weak points have been improved to open the way for innovative new features like near-real-time search, flexible indexing, and high-performance numerical range queries. APIs deprecated from Release 2.9 and its predecessors are removed from the 3.0 release. At the same time, many new features have been added, new APIs introduced, and critical bugs have been fixed—all with the same goal: improving Lucene’s state-of-the-art search capabilities.