The pom.xml contains all the necessary information needed to create the folder structure and pom for the artifact. In fact, if you run Maven in a case where you have specified an artifact which it cannot find in any repositories, you will recieve instructions on how to use the maven-install plugin to add the project.
[INFO] Failed to resolve artifact.
Try downloading the file manually from the project website.
Then, install it using the command:
mvn install:install-file -DgroupId=com.some-company -DartifactId=some-artifact \
-Dversion=1.0.3-SNAPSHOT -Dpackaging=jar -Dfile=/path/to/file
Today, the process is not automatic. However, all the semantics are already made in the pom.xml. All you require is that lib/some-artifact has the same identifier as in the dependency.