Apache Lucene is a high-performance, full featured text search engine library written in Java.

Apache Solr is an enterprise search platform written in Java and using Apache Lucene. Major features include full-text search, index replication and sharding, and result faceting and highlighting.

This README file only contains basic setup instructions. For more comprehensive documentation, visit:

• Lucene: https://lucene.apache.org/core/documentation.html
• Solr: https://lucene.apache.org/solr/guide/

See lucene/BUILD.md.

Firstly, you need to set up your development environment (OpenJDK 11 or greater).

We'll assume that you know how to get and set up the JDK - if you don't, then we suggest starting at https://www.oracle.com/java/ and learning more about Java, before returning to this README. Solr runs with Java 11 and later.

As of 9.0, Lucene/Solr uses Gradle as the build system. Ant build support has been removed.

To build Lucene and Solr, run (./ can be omitted on Windows):

./gradlew assemble

NOTE: DO NOT use gradle command that is already installed on your machine (unless you know what you'll do). The "gradle wrapper" (gradlew) does the job - downloads the correct version of it, setups necessary configurations.

The first time you run Gradle, it will create a file "gradle.properties" that contains machine-specific settings. Normally you can use this file as-is, but it can be modified if necessary.

The command above packages a full distribution of Solr server; the package can be located at:

solr/packaging/build/solr-*

Note that the gradle build does not create or copy binaries throughout the source repository so you need to switch to the packaging output folder above; the rest of the instructions below remain identical. The packaging directory is rewritten on each build.

For development, especially when you have created test indexes etc, use the ./gradlew dev task which will copy binaries to ./solr/packaging/build/dev but only overwrite the binaries which will preserve your test setup.

If you want to build the documentation, type ./gradlew -p solr documentation.

After building Solr, the server can be started using the bin/solr control scripts. Solr can be run in either standalone or distributed (SolrCloud mode).

To run Solr in standalone mode, run the following command from the solr/ directory:

bin/solr start

To run Solr in SolrCloud mode, run the following command from the solr/ directory:

bin/solr start -c

The bin/solr control script allows heavy modification of the started Solr. Common options are described in some detail in solr/README.txt. For an exhaustive treatment of options, run bin/solr start -h from the solr/ directory.

• IntelliJ - IntelliJ idea can import the project out of the box. Code formatting conventions should be manually adjusted.
• Eclipse - Not tested.
• Netbeans - Not tested.

./gradlew assemble will build a runnable Solr as noted above.

./gradlew check will assemble Lucene/Solr and run all validation tasks unit tests.

./gradlew help will print a list of help commands for high-level tasks. One of these is helpAnt that shows the gradle tasks corresponding to ant targets you may be familiar with.

Please review the Contributing to Solr Guide for information on contributing.

• Users Mailing List
• Developers Mailing List
• Lucene Issue Tracker
• Solr Issue Tracker
• IRC: #solr and #solr-dev on freenode.net