Re: Why use Spring?
Several applications start as a small projects and later on grow bigger.
So if a bunch of developers continuously adding new features without considering dependencies or introducing new dependencies on other modules or features soon the application maintenance will become a nightmare.
Spring framework encourages some good design and coding principles like IOC, Coding to Interfaces etc etc.
While you trying to migrate from your legacy application to spring based application, you will automatically separate out the dependencies and inject them through IOC thereby your application design will be clean, clear and maintainable.
And also the major advantage is Spring framework will take care of providing Infrastructural services like Transaction Management, Integration to Other Frameworks etc. Also Spring provides several Template classes which saves lot of time from writing boilerplate code by yourself.
Finally my point is if your application is live and growing(adding new functionality) it is very much worthful to use Spring.
K. Siva Prasad Reddy