can just migrate from spring 2.5 to spring 3.0?

i'm at my new job and the projects at work are in spring 2.5 (some portlets). how hard is it to migrate to spring 3 ?

there is a customized portal 1.0 (don't know if this is relevant) and i was wondering if i could just ask to develop in spring 3.

never used spring be开发者_StackOverflow社区fore and want to learn some, but it would be nice if i could just go for the latest version. got spring in action 3rd edition and would like to make use of that

It principle, it should be a drop-in replacement. There's a bunch of stuff that was deprecated in Spring 3, and huge amount of new stuff added, but nothing was removed.

However, there were a bunch of minor bug fixes, and your code may be unwittingly relying on the buggy behaviour, so some minor adjustments may be necessary, but nothing any worse than that.

Other than that, the big difference is that Spring 3 requires Java5+. I'm assuming you're not stuck on 1.4 :)