From time to time, we need to work with legacy codes.
Recently I got a chance to look at some old modules. They were developed many years ago, Ant is used as build tool. Each of these modules has its lib folder, which has all the dependent jars. And some of the Ant build scripts have its own “typedef” task and the the typedef task class comes from the module itself. They are left behind comparing to other stuff I work on in term of SDLC stack. I decided to move those modules to Maven first.
To keep it simple, I decided to keep the jars as they are, give it a try with “system” scope. It turns out it works perfectly.

Add local jars as Maven dependencies

<dependency>
    <groupId>io.wwei.sample</groupId>
    <artifactId>stmp</artifactId>
    <version>1.0.0</version>
    <scope>system</scope>
    <systemPath>${basedir}/lib/stmp.jar</systemPath>
</dependency>

Execute Java Classes as part of “package” step

<plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>exec-maven-plugin</artifactId>
    <version>1.4.0</version>
    <executions>
        <execution>
            <id>exec1</id>
            <phase>package</phase>
            <goals>
                <goal>java</goal>
            </goals>
            <configuration>
                <mainClass>io.wwei.sample.PostCompile</mainClass>
                <additionalClasspathElements>
                    <additionalClasspathElement>{basedir}/target/classes</additionalClasspathElement>
                </additionalClasspathElements>
                <classpathScope>system</classpathScope>
                <commandlineArgs>local</commandlineArgs>
            </configuration>
        </execution>
    </executions>
</plugin>

Include local jars to final assembly

“dependencySets” does not include local jars, so we have to copy them explicitily as below

<fileSets>
    <fileSet>
        <directory>lib</directory>
        <outputDirectory>lib</outputDirectory>
        <includes>
            <include>**/*</include>
        </includes>
    </fileSet>
</fileSets>