Frequently_Asked_Questions

Q: Is this repository (https://github.com/maven-nar/nar-maven-plugin) the official home of the NAR plugin?

A: Yes. @duns, the original author, donated the plugin (with Sonatype's approval) to the community, since he no longer has time to maintain it.

Q: Is the NAR project being actively maintained?

A: Yes, it is now. It was rather dormant for the past few years, but now has at least two active maintainers (@ctrueden and @dscho), with a few others participating in the development as well.

Q: Is the NAR project being actively developed?

A: NAR is a volunteer project; no one is paid to work on it full time. So development is driven by community contributions. This means you! If there is a bug or feature you want addressed, we encourage you to file a pull request with your patch. The maintainers are very happy to help you, if you take the first step.

Q: Why was the plugin renamed to nar-maven-plugin?

A: To comply with the permitted usages of the Maven trademark. According to the Apache Project Management Committee:

The pmc is permitting persons who develop plugins for maven to use the mark maven in their plugin name provided the name and its usage meets certain criteria, amongst which is the "___-maven-plugin" naming scheme.

The NAR plugin was previously named `maven-nar-plugin` because it was slated for adoption as an official Maven plugin, but that never happened. So the `artifactId` has been changed to `nar-maven-plugin`. (The `groupId` will need to change as well, but that is still pending.)

Q: Where is the official forum/list?

A: The maven-nar Google group.

Q: Where is the official issue tracker?

A: GitHub Issues. There was a category for NAR in the Sonatype JIRA, which was active until May 2013, but it has apparently been deleted, so we unfortunately cannot migrate those issues to GitHub. If you had filed an issue there which is still relevant to the latest master branch, please file a new GitHub issue for it. Thanks!

Q: Where are the official releases? Are they deployed to Central?

A: Yes, releases are deployed to Sonatype's OSS repository. Version 3.0.0 was released on December 6th, 2013. Version 3.1.0 was released on June 7th, 2014. Maven Central mirrors the Sonatype OSS repository, including the nar-maven-plugin.

Q: Is there a public Maven repository with release builds?

A: Yes, stable releases are now available on Central!

<plugin>
    <groupId>com.github.maven-nar</groupId>
    <artifactId>nar-maven-plugin</artifactId>
    <version>3.0.0</version>
</plugin>

The source for 3.0.0 is tagged on GitHub.

Q: Where can I find a working example of how to configure the NAR plugin?

A: Several open source projects make use of the NAR plugin:

1. DevZendo Cross-Platform FileSystem Access uses NAR. The POM is straightforward and may be a good first project to study for learning about NAR.
2. SLIM-curve uses NAR with some extra configuration, and may be a good second project to study for seeing a few more parameters in action.
3. ImageJ has a native launcher component which uses NAR. Search the pom.xml for "nar" to find the relevant blocks. It is not a simple "hello world" example (e.g., it uses OS-specific profiles), but it is a working real-world use case which successfully builds on a Jenkins server farm including Windows, OS X and Linux nodes.

We would gladly welcome any other working examples of the NAR plugin in use!

Q: How can I test the latest SNAPSHOTs?

A: To use the latest code on the master branch and/or topic branches: clone the code from GitHub, and build it using mvn install. This installs the JAR into your local Maven repository cache (typically at ~/.m2/repository/com/github/maven-nar/nar-maven-plugin/3.0.0-SNAPSHOT). Then add a reference to the plugin within your project's POM:

<plugin>
    <groupId>com.github.maven-nar</groupId>
    <artifactId>nar-maven-plugin</artifactId>
    <version>3.0.0-SNAPSHOT</version>
</plugin>

It will resolve the plugin from your local cache.

Note that this approach is recommended only for testing, not for production code, because anyone else building your code will then also need to build nar-maven-plugin beforehand as well.

Q: How can I test a specific integration test?

A: Call mvn -Prun-its -Dinvoker.test=<directory-name> where <directory-name> is something like it0003-jni.

Q: How can I debug integration tests with, say, Eclipse?

A: First, run the integration test as specified above. Then, create a new file called invoker.properties in target/it/<it-name>/ that contains this line:

invoker.mavenOpts = -agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=localhost:8000

Now, run the integration test again. The JVM launched to run the test should suspend and wait for your next steps.

The next steps are:

1. Fire up Eclipse (or whatever IDE with debugging capabilities you want to use).
2. Create a new Debug Configuration for Remote Debugging, attached to port 8000 and associated with the nar-maven-plugin project, which you imported previously with File>Import>Existing Maven Project (you did, didn't you?).
3. Add any desired breakpoints.
4. Finally, click the Debug button of said debug configuration.