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<!---
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 |****      THIS FILE IS GENERATED BY THE COMMONS BUILD PLUGIN      ****|
 |****                    DO NOT EDIT DIRECTLY                      ****|
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 +======================================================================+
 | TEMPLATE FILE: readme-md-template.md                                 |
 | commons-build-plugin/trunk/src/main/resources/commons-xdoc-templates |
 +======================================================================+
 |                                                                      |
 | 1) Re-generate using: mvn commons-build:readme-md                    |
 |                                                                      |
 | 2) Set the following properties in the component's pom:              |
 |    - commons.componentid (required, alphabetic, lower case)          |
 |    - commons.release.version (required)                              |
 |                                                                      |
 | 3) Example Properties                                                |
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 |  <properties>                                                        |
 |    <commons.componentid>math</commons.componentid>                   |
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Apache Commons Collections
===================

[![Java CI](https://github.com/apache/commons-collections/actions/workflows/maven.yml/badge.svg)](https://github.com/apache/commons-collections/actions/workflows/maven.yml)
[![Maven Central](https://img.shields.io/maven-central/v/org.apache.commons/commons-collections4?label=Maven%20Central)](https://search.maven.org/artifact/org.apache.commons/commons-collections4)
[![Javadocs](https://javadoc.io/badge/org.apache.commons/commons-collections4/4.5.0-M3.svg)](https://javadoc.io/doc/org.apache.commons/commons-collections4/4.5.0-M3)
[![CodeQL](https://github.com/apache/commons-collections/actions/workflows/codeql-analysis.yml/badge.svg)](https://github.com/apache/commons-collections/actions/workflows/codeql-analysis.yml)
[![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/apache/commons-collections/badge)](https://api.securityscorecards.dev/projects/github.com/apache/commons-collections)

The Apache Commons Collections package contains types that extend and augment the Java Collections Framework.

Documentation
-------------

More information can be found on the [Apache Commons Collections homepage](https://commons.apache.org/proper/commons-collections).
The [Javadoc](https://commons.apache.org/proper/commons-collections/apidocs) can be browsed.
Questions related to the usage of Apache Commons Collections should be posted to the [user mailing list](https://commons.apache.org/mail-lists.html).

Getting the latest release
--------------------------
You can download source and binaries from our [download page](https://commons.apache.org/proper/commons-collections/download_collections.cgi).

Alternatively, you can pull it from the central Maven repositories:

```xml
<dependency>
  <groupId>org.apache.commons</groupId>
  <artifactId>commons-collections4</artifactId>
  <version>4.5.0-M3</version>
</dependency>
```

Building
--------

Building requires a Java JDK and [Apache Maven](https://maven.apache.org/).
The required Java version is found in the `pom.xml` as the `maven.compiler.source` property.

From a command shell, run `mvn` without arguments to invoke the default Maven goal to run all tests and checks.

Contributing
------------

We accept Pull Requests via GitHub. The [developer mailing list](https://commons.apache.org/mail-lists.html) is the main channel of communication for contributors.
There are some guidelines which will make applying PRs easier for us:
+ No tabs! Please use spaces for indentation.
+ Respect the existing code style for each file.
+ Create minimal diffs - disable on save actions like reformat source code or organize imports. If you feel the source code should be reformatted create a separate PR for this change.
+ Provide JUnit tests for your changes and make sure your changes don't break any existing tests by running `mvn`.
+ Before you pushing a PR, run `mvn` (by itself), this runs the default goal, which contains all build checks.
+ To see the code coverage report, regardless of coverage failures, run `mvn clean site -Dcommons.jacoco.haltOnFailure=false`

If you plan to contribute on a regular basis, please consider filing a [contributor license agreement](https://www.apache.org/licenses/#clas).
You can learn more about contributing via GitHub in our [contribution guidelines](CONTRIBUTING.md).

License
-------
This code is licensed under the [Apache License v2](https://www.apache.org/licenses/LICENSE-2.0).

See the `NOTICE.txt` file for required notices and attributions.

Donating
--------
You like Apache Commons Collections? Then [donate back to the ASF](https://www.apache.org/foundation/contributing.html) to support development.

Additional Resources
--------------------

+ [Apache Commons Homepage](https://commons.apache.org/)
+ [Apache Issue Tracker (JIRA)](https://issues.apache.org/jira/browse/COLLECTIONS)
+ [Apache Commons Slack Channel](https://the-asf.slack.com/archives/C60NVB8AD)
+ [Apache Commons Twitter Account](https://twitter.com/ApacheCommons)

Apache Commons Components
-------------------------

Please see the [list of components](https://commons.apache.org/components.html)
