Page tree
Skip to end of metadata
Go to start of metadata
March 2013, Apache Lucene™ 4.2 available
The Lucene PMC is pleased to announce the release of Apache Lucene 4.2

Apache Lucene is a high-performance, full-featured text search engine
library written entirely in Java. It is a technology suitable for nearly
any application that requires full-text search, especially cross-platform.

This release contains numerous bug fixes, optimizations, and
improvements, some of which are highlighted below. The release
is available for immediate download at:

See the CHANGES.txt file included with the release for a full list of

Lucene 4.2 Release Highlights:

 * Lucene 4.2 has a new default codec (Lucene42Codec) with a more
   efficient docvalues format (sorted bytes in FST, less addressing
   overhead, improved numeric compression) and smaller term
   vectors (LZ4-compressed terms dictionaries and payloads, delta-encoded
   positions and offsets using blocks of packed integers).

 * Doc values external and codec API and implementations have been
   simplified: the codec is no longer responsible for buffering doc
   values; the numerous types have been consolidated down to only
   three (NUMERIC, BINARY, SORTED); PerFieldDocValuesFormat lets you
   set a different format for each field, and the doc values and FieldCache
   APIs were unified.

 * Significant refactoring and performance enhancements to the facet
   module, resulting in overall ~3.8X speedup in one case (single Date
   field faceting).

 * DrillDownQuery in the facet module now supports multi-select.

 * A new DrillSideways class enables counting facet labels and counts
   for both hits and near-misses in a single query.  See

 * An additional docvalues type (SORTED_SET) was added that supports multiple

 * FSTs are a bit smaller, and the FST package supports FSTs over 2GB
   in size.

 * A new LiveFieldValues class lets you get live or real-time values
   for any indexed doc / field.  See

 * Added a new classification module.

 * Various bugfixes and optimizations since the 4.1 release.

Please read CHANGES.txt for a full list of new features.

Please report any feedback to the mailing lists

Note: The Apache Software Foundation uses an extensive mirroring network
for distributing releases.  It is possible that the mirror you are using
may not have replicated the release yet.  If that is the case, please
try another mirror.  This also goes for Maven access.
  • No labels