Java: how to move common functionality into a separate package?

Question

Java

Hello! I'm new to Java, so don't judge too hard.
I have several java applications (server, android application, desktop) that use the same classes. I would like to put them in separate packages, and so that they are automatically synchronized between applications. How is it better to do this? For assembly I use Gradle, IDE - Idea.
Thanks in advance!

Answer 1

Collect everything in a separate lib (project-common.jar) and add it to all projects as a dependency ..
PS. In Gradle or Maven, I usually make modules.