lucene/README.md

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# Apache Lucene

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

[![Build Status](https://ci-builds.apache.org/job/Lucene/job/Lucene-Artifacts-master/badge/icon?subject=Lucene)](https://ci-builds.apache.org/job/Lucene/job/Lucene-Artifacts-master/) [![Build Status](https://ci-builds.apache.org/job/Lucene/job/Solr-Artifacts-master/badge/icon?subject=Solr)](https://ci-builds.apache.org/job/Lucene/job/Solr-Artifacts-master/)

## 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

### Building Lucene

See [lucene/BUILD.md](./lucene/BUILD.md).

### Building Solr

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](https://gradle.org/) 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`.

## Running Solr

After [building Solr](#building-lucene-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.

### 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 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.

## Contributing

Please review the [Contributing to Solr
Guide](https://cwiki.apache.org/confluence/display/solr/HowToContribute) for information on
contributing.

## Discussion and Support

- [Users Mailing List](http://lucene.apache.org/solr/community.html#solr-user-list-solr-userluceneapacheorg)
- [Developers Mailing List](http://lucene.apache.org/solr/community.html#developer-list-devluceneapacheorg)
- [Lucene Issue Tracker](https://issues.apache.org/jira/browse/LUCENE)
- [Solr Issue Tracker](https://issues.apache.org/jira/browse/SOLR)
- IRC: `#solr` and `#solr-dev` on freenode.net