What you want to investigate is Maven’s dependency plugin. Add something similar to the following to pom.xml:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<configuration>
<outputDirectory>
${project.build.directory}
</outputDirectory>
</configuration>
</plugin>
Then run mvn clean dependency:copy-dependencies
to copy perform the copy. Combine this with the assembly plugin and you can package everything into a self contained archive for distribution.