I'm not sure now, but 10 years ago I was really feeling the impact of compilation in eclipse. On a big project that I was working on it was taking about 20 minutes for a full build and I had to disable the background compilation because it always messed up stuff and my code would be out of synch. I think that in general Java compilation feels a bit faster, but for sure you can't say that you don't feel it at all in big projects.