Question

In the following senario

I’m wrapping an external jar file (read a dependency I’ve no control over) and wrapping this in a service to be exposed over RMI.

I’d like my service interface to also be exported as a maven dependency however as it will be returning classes defined in the dependency this means that the dependency itself will be used as a dependency of my service interface.

Unfortunatly the origional jar file contains many classes that are not relevant to my exposed service.

Is it possible to depend on just a few classes in that jar file in maven (possibly by extracting and repackaging the few classes that are relevant)?

• uberbig_irrelevant.jar
  • com.uberbig.beans <– Need this package or a few classes in it.
  • com.uberbig.everythingElse

Service project includes all of uberbig jar. But exposes a service BeanService which has a call which returns an insance of com.uberbig.beans.IntrestingLightWeightSerialiasbleBean.

Service interface project needs to have a bean definition that looks like

interface BeanFetcher {
   public IntrestingLightWeightSerialiasbleBean fetchBeanById(long beanId);
}

So ideally my serviceInterface jar file would only include the BeanFetcher interface. The definition of IntrestingLightWeightSerialiasbleBean and any direct dependencies of IntrestingLightWeightSerialiasbleBean.

The project is for use internally and won’t be publically exposed so there should be no problems repackaging so long as the repackaged bean definitions are binary and searially compatable with the external jar file.

Any Suggestions?

Possibly related question Maven depend on project – no jar but classes

Maybe I could use something from the dependency:copy section of the maven-dependency-plugin but I haven’t figured out how to do that.

Answer 1

I think you got the plugin right, but not the goal. You should use dependency:unpack instead.

You should be able to use an inclusion filter to extract only the classes you need, and then repack them into your own jar. (The service interface jar if you do it in the service interface project, but you can just as well set up a separate project.)