solr  9.0.0
About: Solr is the search platform from the Apache Lucene project. Its major features include full-text search, hit highlighting, faceted search, caching, replication, and a web admin interface. Java source code.
The most recent release (9.x series).
  Fossies Dox: solr-9.0.0-src.tgz  ("unofficial" and yet experimental doxygen-generated source code documentation)  

solr Documentation

Some Fossies usage hints in advance:

  1. To see the Doxygen generated documentation please click on one of the items in the steelblue colored "quick index" bar above or use the side panel at the left which displays a hierarchical tree-like index structure and is adjustable in width.
  2. If you want to search for something by keyword rather than browse for it you can use the client side search facility (using Javascript and DHTML) that provides live searching, i.e. the search results are presented and adapted as you type in the Search input field at the top right.
  3. Doxygen doesn't incorporate all member files but just a definable subset (basically the main project source code files that are written in a supported language). So to search and browse all member files you may visit the Fossies solr-9.0.0-src.tgz contents page and use the Fossies standard member browsing features (also with source code highlighting and additionally with optional code folding).

Apache Solr

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.

Build Status

Online Documentation

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

Building with Gradle

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 and learning more about Java, before returning to this README. Solr runs with Java 11 and later.

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

To build 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 "" 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:


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.

Running Solr

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

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

bin/solr start

To run Solr in clustered 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.

Running Solr in Docker

You can run Solr in Docker via the official image.

To run Solr in a container and expose the Solr port, run:

docker run -p 8983:8983 solr

In order to start Solr in clustered mode, run the following.

docker run -p 8983:8983 solr solr-fg -c

For documentation on using the official docker builds, please refer to the DockerHub page.
Up to date documentation for running locally built images of this branch can be found in the local reference guide.

There is also a gradle task for building custom Solr images from your local checkout. These local images are built identically to the official image except for retrieving the Solr artifacts locally instead of from the official release. This can be useful for testing out local changes as well as creating custom images for yourself or your organization. The task will output the image name to use at the end of the build.

./gradlew docker

For more info on building an image, run:

./gradlew helpDocker

Docker images can also be built from the Solr binary distribution (i.e. solr-<version>.tgz). Please refer to the Solr Docker README for more information.

Running Solr on Kubernetes

Solr has official support for running on Kubernetes, in the official Docker image. Please refer to the Solr Operator home for details, tutorials and instructions.

Gradle build and IDE support

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

Gradle build and tests

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

./gradlew check will assemble 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.

Discussion and Support