How to create an additional attached jar artifact from the project
Specify a list of fileset patterns to be included or excluded by adding <includes>/<include> or <excludes>/<exclude> and add a classifier in your pom.xml.
Note: the jar-plugin must be defined in a new execution, otherwise it will replace the default use of the jar-plugin instead of adding a second artifact. The classifier is also required to create more than one artifact.
<project>
...
<build>
<plugins>
...
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.4.2</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>jar</goal>
</goals>
<configuration>
<classifier>client</classifier>
<includes>
<include>**/service/*</include>
</includes>
</configuration>
</execution>
</executions>
</plugin>
...
</plugins>
</build>
...
</project>