What is the purpose of providing a downloaded pom.xml on mvnrepository.com

Question

On mvnrepositry, when you search for a certain module, there's a link to download the binary. For some versions it has a pom.xml file available for download instead of the jar. What are you supposed to do with that pom.xml? It seems like if I specify a version that does not have a downloadable jar, but instead downloadable pom.xml, my maven build will fail. Is what I'm seeing correct?

Answer 1

One of the reason that cause this is because of licensing issue.

License for such JARs prohibit public redistribution in such approach. So someone provide only the POM so that you can get the JAR yourself and install it to your local maven repo/ internal repo, together with the POM provided.

Answer 2

Modules that only have pom files are maven modules with pom packaging. They are used to aggregate multiple modules into one unit. You can use such a module as a dependency for your maven project. Maven will download the pom file, analyze the dependencies included in that pom file and download those & add it to your automatically.

Even modules that have jars (jar packaging) have a pom file associated with them. This pom file defines the other dependencies that are required for using it. Maven will automatically process and fetch those dependencies (transitive dependencies).

This makes specifying and managing dependency for any project. You will specify the top level modules that your projects directly depends on and other things required will automatically figured out and downloaded. It also makes it easier when you have upgrade to a new version - all the transitive dependencies will get upgraded automatically.