Managing common values for multiple Maven archetypes

Question

I have a number of Maven archetypes, structured as follows

.
├── bundle
├── bundle-for-jcrinstall
├── initial-content
├── launchpad-standalone
├── launchpad-webapp
├── servlet
└── taglib

For these, I would like to have a single source of common values, e.g. plugin versions, so that I can change them in just one place for all modules. The changes should end up in the generated pom.xml, so I would define e.g. bundle/src/main/resources/archetype-resources/pom.xml containing

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.felix</groupId>
            <artifactId>maven-scr-plugin</artifactId>
            <version>${scrplugin.version}</version>
            <executions>
                <execution>
                    <id>generate-scr-descriptor</id>
                    <goals>
                        <goal>scr</goal>
                    </goals>
                </execution>
            </executions>
  <!-- snip ... -->

And then supply the value in the bundle/pom.xml file, ideally inherited from a parent pom . The problem is, I have no idea how to supply this value in bundle/pom.xml so that it becomes available to the generate pom.xml file.

Any ideas on how to do that, or other ways of solving this problem are more than appreciated.

Answer 1

Resource file filtering isn't on by default, so you have to turn it on.

In the pom of your parent project; add the property you want:

<scrplugin.version>1.14.0</scrplugin.version>

In the archetype pom, add a resource filtering (assuming you're using the standard Maven organization)

<build>
    <resources>
        <resource>
            <directory>src/main/resources</directory>
            <filtering>true</filtering>
            <includes>
                <include>**/*</include>
            </includes>
        </resource>
    </resources>
    <extensions>
        <extension>
            <groupId>org.apache.maven.archetype</groupId>
            <artifactId>archetype-packaging</artifactId>
            <version>2.2</version>
        </extension>
    </extensions>

    <pluginManagement>
        <plugins>
            <plugin>
                <artifactId>maven-archetype-plugin</artifactId>
                <version>2.2</version>
            </plugin>
        </plugins>
    </pluginManagement>
</build>

This will process your poms to replace any properties that you have defined; leaving any you don't as-is. This will put the property into the archetype's output jar, so it will be a set version whenever you use that archetype library when running the archetype:generate command.

Hope that helps.

-Stopp