Question

I have a question that’s probably pretty similar to this. I need to solve what I have to imagine to be a pretty common problem — how to configure Maven to produce multiple variations on the same artifact — but I have yet to find a good solution.

I have a multi-module project, that eventually results in the assembly plugin generating an artifact. However, part of the assembly includes libraries that have changed substantially in the recent past, with the result that some consumers of the project need library version N, while others need version N+1. Ideally, we’d just automatically generate multiple artifacts, e.g. theproject-1.2.3.thelib-1.0.tar.gz, theproject-1.2.3.thelib-1.1.tar.gz, etc. (where that’s release 1.2.3 of our project, running against either library version 1.0 or 1.1).

Right now, I have a bunch of default properties, which build against the latest version of the library in question, plus a profile to build against the older version. I can deploy one or the other this way, but cannot deploy both in one build. Here’s the key wrinkle that differs from the above question: I can’t automate build-one-clean-build-the-other inside of the release plugin.

Normally, we’d mvn release:prepare release:perform from the root of the multi-module project to take care of deploying everything to our internal Nexus. However, in that case, we have to pick one — either run the old-library profile, or run without and get the new one. I need the release plugin to deploy both. Is this just impossible? I have to imagine we’re not the first people who want to have our automated builds generate support for different platforms….

Answer 1

You may install additional artifacts with differrent types/classifiers. Use attach-artifact goal of the build-helper-maven-plugin to achieve this. Here is a small example – we are deploying a Windows and a Unix installers of the product as windows/exe and unix/sh files. These files will be installed to the local repo and deploy to the distribution management.

<plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>build-helper-maven-plugin</artifactId>
    <executions>
        <execution>
            <id>install-installation</id>
            <phase>install</phase>
            <goals>
                <goal>attach-artifact</goal>
            </goals>
            <configuration>
                <artifacts>
                    <artifact>
                        <file>${basedir}/target/${project.artifactId}-${project.version}-windows.exe</file>
                        <classifier>windows</classifier>
                        <type>exe</type>
                    </artifact>
                    <artifact>
                        <file>${basedir}/target/${project.artifactId}-${project.version}-unix.sh</file>
                        <classifier>unix</classifier>
                        <type>sh</type>
                    </artifact>
                </artifacts>
            </configuration>
        </execution>
    </executions>
</plugin>

Hope this helps.