Maven: Using JUnit with DLLs

Since I was unable to quickly google the solution for my Maven DLL problem, I thought I'd post a quick blog about it. Here's the situation, I have tests that rely on artifacts that are DLLs (in my case these were the Java3D DLLs). So, I needed to be able to have the DLLs in a known location so that the tests could run, but did not want to check those items into the SCM repository, nor install them locally on the Hudson server. I made two changes to the POM file.

First I used the dependency plugin to find and output all the DLLs.

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-dependency-plugin</artifactId>
    <version>2.1</version>
    <executions>
        <execution>
            <id>copy-dlls</id>
            <phase>process-test-resources</phase>
            <goals>
                <goal>copy-dependencies</goal>
            </goals>
            <configuration>
                <includeTypes>dll</includeTypes>
                <excludeTypes>*</excludeTypes>
                <stripVersion>true</stripVersion>
                <silent>true</silent>
                <outputDirectory>${project.build.directory}/dll</outputDirectory>
                <overWriteReleases>false</overWriteReleases>
                <overWriteSnapshots>false</overWriteSnapshots>
                <overWriteIfNewer>true</overWriteIfNewer>
            </configuration>
        </execution>
    </executions>
</plugin>

Then, I modified the surefire plugin to use the output directory as part of the java.library.path.

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <configuration>
        ...
        <argLine>-Djava.library.path=${basedir}/target/dll</argLine>
    </configuration>
</plugin>

Hopefully, this will make it easier for the next guy trying to solve the same problem. If anyone has a better way of doing it, please let me know.