Removing unnessary classes from third party libraries and JARs [duplicate]

Question

I need to remove unused classes from third party JARs. Why tools should I use?

I already tried to use ProGuard. However, it removes only unused classes from the project itself but the library jars - third party - always remain unchanged.

Answer 1

You can create an uber jar and then use ProGuard. Repackaging library classes into jars would be a challenge, but from the spirit of your question you will prefer the uber jar as such.

As other posters have commented, you still need to be careful about classes loaded through the so much abused and misunderstood reflection mechanism.