Making jar from custom sourceset

Help/Discuss
1

I have a project which was not constructed using Gradle before, and I am adding Gradle to it.
(I have seem something similar but not quite sure how to apply to my case Gradle: custom source set as dependency for the main and test ones)
The original source folders are separated, so I added something similar to the following.

sourceSets {

      cus{
        java {
            srcDir 'cus'
        }

      }

   adm{
        java {
            srcDir 'adm'
        }

      }
	  
	 common{
        java {
            srcDir 'common'
        }

      }
}

Note: I do not have a “main” sourceSet.

Now I want package each sourceSet into a separate jar, and have the following (each sourceSet do have dependencies on each other)

task cusJar(type: Jar) {
    
    from(sourceSets.cus.output) {
        include '**/*.class'
    }
	
}

When I execute this, Gradle will also execute “compileCusJava”, but this task will fail, because it cannot find any of the jar files I defined in “dependencies” or other sourseSet.
How do I set this up correctly and efficiently?

Note: When I do “compileJava” everything is fine.

2

How did you configure the dependency to other sourceSets?

Have you used something like:

sourceSets {
    adm
    cus{
        compileClasspath += sourceSets.adm.output
    }
 }
3

No, I did not do that, at least not yet.
Because all my source folders have dependencies depends on each other, so I was wondering do I have to do that for all the sourceSets?

So I must do something like this for all my sourceSet? and if I add another one I have to add it to all other sourceSets? Or is there a more clever way of doing this?

sourceSets {

      cus{
        java {
            srcDir 'cus'
        }
        compileClasspath += sourceSets.adm.output + sourceSets.wkf.output + sourceSets.common.output
      }

   adm{
        java {
            srcDir 'adm'
        }

        compileClasspath += sourceSets.cus.output + sourceSets.wkf.output + sourceSets.common.output

      }
}
4

for common configurations you can do something like this:

sourceSets.all{
    compileClasspath += sourceSets.common.output
}

and then do the specific configurations per sourceSet. Why do you have
so many sourceSets? Maybe this could be better modeled using projects.

5

This is an old project and we were trying separate modules into different source folders and package them into different jars show our modularity.
I can see separating them into project sounds good, but there will be lots circular dependencies between the projects, not sure if it will cause problems.
Also, I am trying to preserve how the project presents in our Eclipse. (this is a good-to-have option but not necessary)