I have lilbit experience with spring2.5, but i dont know end to end of spring2.5. How difficult it is to migrate my application to spring3? can i migrate only sopme parts to spring3 and retain others to spring2.5?
For the most part, Spring 3 is backward compatible with Spring 2.5. It shouldn't be hard at all to move to Spring 3. There are a few minor differences,but honestly...I have never run into them and so I don't remember them.
The key thing that does come to mind is that historically Spring has always come with an uber spring.jar file and then several individual module files. Spring 3 did away with the uber JAR--if you're using it, then you'll have to hand pick the individual modules.