Today Apache Lucene and Solr PMC announced another version of Apache Lucene library and Apache Solr search server numbered 4.9. This is a next release continuing the 4th version of both Apache Lucene and Apache Solr.
Here are some of the changes that were made comparing to the 4.8.1:
Lucene
- New default format – Lucene49NormsFormat
- Numerous search time doc values performance improvements
- New posting format (IDVersionPostingsFormat) optimized for fields holding unique identifiers
- All Lucene files are now written using OutputStream on all platforms
Solr
- Support for re-ranking top N query results
- New doc transformer allowing to include nested documents in results
- Ability to specify minimal replication factor for an update request
- Optimizations and bugfixes from Lucene 4.9
Full changes list for Lucene can be found at http://wiki.apache.org/lucene-java/ReleaseNote49. Full list of changes in Solr 4.8 can be found at: http://wiki.apache.org/solr/ReleaseNote49.
Apache Lucene 4.9 library can be downloaded from the following address: http://www.apache.org/dyn/closer.cgi/lucene/java/. Apache Solr 4.9 can be downloaded at the following URL address: http://www.apache.org/dyn/closer.cgi/lucene/solr/. Please remember that the mirrors are just starting to update so not all of them will contain the 4.9 version of Lucene and Solr.