Apache Commons Collections =================== [](https://github.com/apache/commons-collections/actions/workflows/maven.yml) [](https://maven-badges.herokuapp.com/maven-central/org.apache.commons/commons-collections4/?gav=true) [](https://javadoc.io/doc/org.apache.commons/commons-collections4/4.5.0-M2) [](https://github.com/apache/commons-collections/actions/workflows/codeql-analysis.yml) [](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 org.apache.commons commons-collections4 4.5.0-M2 ``` 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)