Apache Lucene and Solr 4.4

Today Apache Lucene and Solr PMC announced another version of Apache Lucene library and Apache Solr search server numbred 4.4. 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 4.3 and 4.3.1 versions:


  • New replicator module that allows to replicate Lucene indices
  • AnalyzingInfixSuggester – finds suggestions using matches on any tokens, not only on prefix matches
  • FieldCache improvements – Ints and Longs are now using bit-packaging to save memory and memory usage for high cardinality string fields were improved
  • New features to Lucene faceting module, like dynamic numeric range faceting and hierarchy merging
  • ScandinavianFoldingFilter and ScandinavianNormalizationFilter were introduced
  • New SimpleMergeSegmentWarmer which ensures that internal data structures like term dictionary, docvalues are initialized
  • Compound file format is used by default by IndexWriter to flush segments
  • Known bugfixes and improvements


  • Ability to store and read Solr indices and transaction log directly from HDFS
  • Solr supports schemaless mode – Solr is able to guess the type of the field and add it to your schema.xml – no need to create the schema.xml upfront anymore. The example of schemaless mode can be found in the Apache Solr 4.4 distribution.
  • Support for creating copy fields using Schema API
  • New solr.xml file format allows for core discovery – instead of storing core information it searches for core.properties files
  • You can now upload binary files to ZooKeeper when using SolrCloud
  • You can now add documents to Solr by using Solr administration UI
  • In SolrCloud an Overseer can optionaly assign generic node names to avoid naming confusion
  • New information handler was added that exposes system information
  • Enchantments that comes with Apache Lucene 4.4

Full changes list for Lucene can be found at http://wiki.apache.org/lucene-java/ReleaseNote44. Full list of changes in Solr 4.4 can be found at: http://wiki.apache.org/solr/ReleaseNote44.

Apache Lucene 4.4 library can be downloaded from the following address: http://www.apache.org/dyn/closer.cgi/lucene/java/. Apache Solr 4.4 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 4.4 version of Lucene and Solr.