问题:

We have a small project with some heavy-weight dependencies (e.g. Spring) of which we only use small parts. Therefore, the JAR we get when packing with all dependencies weighs several megabytes, even for out two-class-server. This seems unnecessary.

Is there a way to restrict JAR assembly to actually used (class) files?

回答1:

You can use the maven-shade-plugin to create a Jar-with-dependencies (your project and the dependencies merged into one big jar) while limiting the classes or packages that are added to that jar. See the includes / excludes page for reference.

If you don't want to manually specify what needs to be included, perhaps there is a way to integrate ProGuard with your build.

回答2:

It's not possible to include only classes which are used. But you can exclude dependencies from your depencies to reduce the JAR size. Only drawback: you need to know what you can exclude and what not.