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 |****      THIS FILE IS GENERATED BY THE COMMONS BUILD PLUGIN      ****|
 |****                    DO NOT EDIT DIRECTLY                      ****|
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 | TEMPLATE FILE: contributing-md-template.md                           |
 | commons-build-plugin/trunk/src/main/resources/commons-xdoc-templates |
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 | 1) Re-generate using: mvn commons-build:contributing-md              |
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 | 2) Set the following properties in the component's pom:              |
 |    - commons.jira.id  (required, alphabetic, upper case)             |
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 | 3) Example Properties                                                |
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 |  <properties>                                                        |
 |    <commons.jira.id>MATH</commons.jira.id>                           |
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Contributing to Apache Commons Imaging
======================

Have you found a bug or have an idea for a cool new feature? Contributing code is a great way to give something back to the open-source community.
Before you dig right into the code, we need contributors to follow a few guidelines to have a chance of keeping on top of things.

Getting Started
---------------

+ Make sure you have a [JIRA account](https://issues.apache.org/jira/).
+ Make sure you have a [GitHub account](https://github.com/signup/free). This is not essential, but makes providing patches much easier.
+ If you're planning to implement a new feature it makes sense to discuss your changes on the [dev list](https://commons.apache.org/mail-lists.html) first. This way you can make sure you're not wasting your time on something that isn't considered to be in Apache Commons Imaging's scope.
+ Submit a [Jira Ticket][jira] for your issue, assuming one does not already exist.
  + Clearly describe the issue including steps to reproduce when it is a bug.
  + Make sure you fill in the earliest version that you know has the issue.
+ Find the corresponding [repository on GitHub](https://github.com/apache/?query=commons-),
[fork](https://help.github.com/articles/fork-a-repo/) and check out your forked repository. If you don't have a GitHub account, you can still clone the Commons repository.

Making Changes
--------------

+ Create a _topic branch_ for your isolated work.
  * Usually you should base your branch from the `master` branch.
  * A good topic branch name can be the JIRA bug ID plus a keyword, e.g. `IMAGING-123-InputStream`.
  * If you have submitted multiple JIRA issues, try to maintain separate branches and pull requests.
+ Make commits of logical units.
  * Make sure your commit messages are meaningful and in the proper format. Your commit message should contain the key of the JIRA issue.
  * For example, `[IMAGING-123] Close input stream sooner`
+ Respect the original code style:
  + Only use spaces for indentation; you can check for unnecessary whitespace with `git diff` before committing.
  + 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 first.
+ Write unit tests that match behavioral changes, where the tests fail if the changes to the runtime are not applied. This may not always be possible but is a best-practice.
Unit tests are typically in the `src/test/java` directory.
+ Run a successful build using the default [Maven](https://maven.apache.org/) goal with `mvn`; that's `mvn` on the command line by itself.
+ Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
+ Each commit in the pull request should have a meaningful subject line and body. Note that commits might be squashed by a maintainer on merge.


Making Trivial Changes
----------------------

The JIRA tickets are used to generate the changelog for the next release.

For changes of a trivial nature to comments and documentation, it is not always necessary to create a new ticket in JIRA.
In this case, it is appropriate to start the first line of a commit with '[doc]' or '[javadoc]' instead of a ticket number.


Submitting Changes
------------------

+ Sign and submit the Apache [Contributor License Agreement][cla] if you haven't already.
  * Note that small patches & typical bug fixes do not require a CLA as
    clause 5 of the [Apache License](https://www.apache.org/licenses/LICENSE-2.0.html#contributions)
    covers them.
+ Push your changes to a topic branch in your fork of the repository.
+ Submit a _Pull Request_ to the corresponding repository in the `apache` organization.
  * Verify _Files Changed_ shows only your intended changes and does not
  include additional files like `target/*.class`
+ Update your JIRA ticket and include a link to the pull request in the ticket.

If you prefer to not use GitHub, then you can instead use
`git format-patch` (or `svn diff`) and attach the patch file to the JIRA issue.


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

+ [Contributing patches](https://commons.apache.org/patches.html)
+ [Apache Commons Imaging JIRA project page][jira]
+ [Contributor License Agreement][cla]
+ [General GitHub documentation](https://help.github.com/)
+ [GitHub pull request documentation](https://help.github.com/articles/creating-a-pull-request/)
+ [Apache Commons Twitter Account](https://twitter.com/ApacheCommons)

[cla]:https://www.apache.org/licenses/#clas
[jira]:https://issues.apache.org/jira/browse/IMAGING