Which web framework to use with portlets?

See also Discussion of portlet development framework selection for portlets delivered as part of uPortal3

Spring

A lot to love here, a learning curve worth climbing, and what's not there you can expect to continue to improve. A framework and a project with a future. And on the learning curve worth climbing point: I think this is an important point, that investing time and energy in learning this framework gains a valuable skill that is applicable to portlet development, to other web application development, to deploying and configuring existing applications. A learning curve worth climbing.

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