Apache Lucene

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

Online Documentation

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

• Lucene: http://lucene.apache.org/core/documentation.html

Building with Gradle

Basic steps:

0. Install OpenJDK 11 (or greater)
1. Download Lucene from Apache and unpack it
2. Connect to the top-level of your installation (parent of the lucene top-level directory)
3. Run gradle

Step 0) 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. Lucene runs with Java 11 and later.

Lucene uses Gradle for build control.

NOTE: Lucene changed from Ant to Gradle as of release 9.0. Prior releases still use Ant.

Step 1) Checkout/Download Lucene source code

We'll assume you already did this, or you wouldn't be reading this file. However, you might have received this file by some alternate route, or you might have an incomplete copy of the Lucene, so: you can directly checkout the source code from GitHub:

https://github.com/apache/lucene

Or Lucene source archives at particlar releases are available as part of Lucene downloads:

https://lucene.apache.org/core/downloads.html

Download either a zip or a tarred/gzipped version of the archive, and uncompress it into a directory of your choice.

Step 2) Change directory (cd) into the top-level directory of the source tree

The parent directory for Lucene contains the base configuration file for the build. By default, you do not need to change any of the settings in this file, but you do need to run Gradle from this location so it knows where to find the necessary configurations.

Step 3) Run Gradle

Assuming you can exectue "./gradlew help" should show you the main tasks that can be executed to show help sub-topics.

If you want to build Lucene, type:

./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.

./gradlew check will assemble Lucene 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.

If you want to build the documentation, type:

./gradlew documentation

Gradle build and IDE support

• IntelliJ - IntelliJ idea can import the project out of the box. Code formatting conventions should be manually adjusted.
• Eclipse - Basic support (help/IDEs.txt).
• Netbeans - Not tested.

Contributing

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

Discussion and Support

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