One way of creating multiple artifacts from Gradle that are consumable by Maven projects is to divide the project in modules and allow each module to publish an artifact that is consumable by Maven.
This sample project show one implementation.
The complete story, with all details, is available at Think Code AB's blog
It is a commandline tool that will reflect a beam in a mirror. Some people mihght call it a Hello world project. It is a starting point with focus on the build tool.
A multimodule project need two or more modules.
The application module. This is the final application. It is built as a war project. Currently it only supports commandline. But one day, you may be able to add it to a servlet container if you want. You will need to put some more work into transforming it first.
A module that is expected to be consumed by other projects as well that need a compile time dependency to a way to communicate with this application. It is distributed as a jar.
The project is built using Gradle wrapper.
./gradlew clean build
Publishing the project to a local Maven repository is done with
publishToMavenLocal
There is no support for publishing to Nexus. This is left as an exercise for the reader. The real reason is that I don't have a Nexus or Artifactory to connect to so I won't speculate in the details.