Maven 2 assembly with dependencies: jar under scope "system" not included.

Question

Hello,

I am using maven-assembly plugin to create a jar of my application, including its dependencies as follows:

<assembly>
    <id>macosx</id>
    <formats>
       <format>tar.gz</format>
       <format>dir</format>
    </formats>
    <dependencySets>
        <dependencySet>
            <includes>
                <include>*:jar</include>
            </includes>
            <outputDirectory>lib</outputDirectory>
        </dependencySet>
    </dependencySets>
</assembly>

(I omitted some other stuff that is not related to the question)

So far this has worked fine because it creates a lib directory with all dependencies. However, I recently added a new dependency whose scope is system, and it does not copy it to the lib output directory. i must be missing something basic here, so I call for help.

The dependency that I just added is:

<dependency>
  <groupId>sourceforge.jchart2d</groupId>
  <artifactId>jchart2d</artifactId>
  <version>3.1.0</version>
  <scope>system</scope>
  <systemPath>${project.basedir}/external/jchart2d-3.1.0.jar</systemPath>
</dependency>

The only way I was able to include this dependency was by adding the following to the assembly element:

<files>
    <file>
        <source>external/jchart2d-3.1.0.jar</source>
        <outputDirectory>lib</outputDirectory>
    </file>
</files>

However, this forces me to change the pom and the assembly file whenever this jar is renamed, if ever. Also, it seems just wrong.

I have tried with <scope>runtime</scope> in the dependencySets and <include>sourceforge.jchart2d:jchart2d</include> with no luck.

So how do you include a system scoped jar to your assembly file in maven 2?

Thanks a lot

Answer 1

I'm not surprised that system scope dependencies are not added (after all, dependencies with a system scope must be explicitly provided by definition). Actually, if you really don't want to put that dependency in your local repository (for example because you want to distribute it as part of your project), this is what I would do:

• I would put the dependency in a "file system repository" local to the project.

• I would declare that repository in my pom.xml like this:

  <repositories>
    <repository>
      <id>my</id>
      <url>file://${basedir}/my-repo</url>
    </repository>
  </repositories>
  

• I would just declare the artifact without the system scope, this is just a source of troubles:

  <dependency>
    <groupId>sourceforge.jchart2d</groupId>
    <artifactId>jchart2d</artifactId>
    <version>3.1.0</version>
  </dependency>
  

I'm not 100% sure this will suit your needs but I think it's a better solution than using the system scope.

Update: I should have mentioned that in my original answer and I'm fixing it now. To install a third party library in the file-based repository, use install:install-file with the localRepositoryPath parameter:

mvn install:install-file -Dfile=<path-to-file> \
                         -DgroupId=<myGroup> \
                         -DartifactId=<myArtifactId> \
                         -Dversion=<myVersion> \
                         -Dpackaging=<myPackaging> \
                         -DlocalRepositoryPath=<path-to-my-repo>

You can paste this as is in a *nix shell. On windows, remove the "\" and put everything on a single line.

Answer 2

Btw you can automate it and make it a part of your maven build. The following will install your jar into your local repository before compilation:

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-install-plugin</artifactId>
            <executions>
                <execution>
                    <id>hack-binary</id>
                    <phase>validate</phase>
                    <configuration>
                        <file>${basedir}/lib/your-lib.jar</file>
                        <repositoryLayout>default</repositoryLayout>
                        <groupId>your-group</groupId>
                        <artifactId>your-artifact</artifactId>
                        <version>0.1</version>
                        <packaging>jar</packaging>
                        <generatePom>true</generatePom>
                    </configuration>
                    <goals>
                        <goal>install-file</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>