Maven assembly : add different version of the same artifact

Question

I create my application archive with the maven assembly plugin. All the dependency present in my pom are included without any problem.

Now I need to include two or more version of the same artifact.

If in my pom I put

<dependencies>
        [...]
        <dependency>
            <groupId>db.test</groupId>
            <artifactId>my-model</artifactId>
            <version>1.0.3</version>
        </dependency>
        <dependency>
            <groupId>db.test</groupId>
            <artifactId>my-model</artifactId>
            <version>1.1.0</version>
        </dependency>
</dependencies>

Of source the dependenvcy resolver remove the old version and only the 1.1.0 is packaged in the archive

I try to include the jar by using assembly xml descriptor file. And I didn't find any solution.

A possible solution will be to manually put all the needed model.jar inside a folder and tell the assembly to copy it in the archive. But I'm looking for a more configurable solution.

Any idea ?

Answer 1

I found a solution by using maven-dependency-plugin to copy resolved pom dependencies and additional jar.

<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.1</version>
<executions>
    <execution>
        <id>copy-dependencies</id>
        <phase>package</phase>
        <goals>
            <goal>copy-dependencies</goal>
        </goals>
        <configuration>
            <outputDirectory>${project.build.directory}/lib</outputDirectory>
            <overWriteReleases>false</overWriteReleases>
            <overWriteSnapshots>false</overWriteSnapshots>
            <overWriteIfNewer>true</overWriteIfNewer>
            <includeScope>runtime</includeScope>
        </configuration>
    </execution>
    <execution>
        <id>copy-model</id>
        <phase>package</phase>
        <goals>
            <goal>copy</goal>
        </goals>
        <configuration>
            <artifactItems>
                <artifactItem>
                    <groupId>my.test.pkg</groupId>
                    <artifactId>my-model</artifactId>
                    <classifier>server</classifier>
                    <version>1.0.3</version>
                    <type>jar</type>
                </artifactItem>
                <artifactItem>
                    <groupId>my.test.pkg</groupId>
                    <artifactId>my-model</artifactId>
                    <classifier>server</classifier>
                    <version>1.1.0</version>
                    <type>jar</type>
                </artifactItem>
            </artifactItems>
            <outputDirectory>${project.build.directory}/lib</outputDirectory>
        </configuration>
    </execution>
</executions>

Now I just have to add the following lines in my assembly xml

    <fileSet>
        <directory>${project.build.directory}/lib</directory>
        <outputDirectory>/lib</outputDirectory>
        <filtered>false</filtered>
        <includes>
            <include>*.jar</include>
        </includes>
        <fileMode>0600</fileMode>
    </fileSet>

Answer 2

Maven assumes it doesn't make any sense to have more than one version of a module at once. It assumes that a newer version replaces the older version. If it doesn't it is not the same module. I suggest you give the newer module a different name and make sure it has different packages to avoid choising a random module.

In general Maven tried to encourage good application design and deliberately makes it difficult to do things it has determined to be a bad idea.