What java based CMS can manage existing pages'

We have an existing and running java web application, currently the pages' content is static but the pages are still jsp files, they have look and feel designed specifically. My customer now wants to use CMS to manage the update of content like news, events with the minimal changes to the jsp code, I tried opencms and haven't found yet it can do that. As much as I know pages are needed to create through opencms ade in opencms world. The layout,look and feel must follow the pattern of opencms , that being said many block contents on pages.Is there any kind of CMS which can match my requirements out of the world?

OpenCms and Magnolia are leading open source java-based CMS. They can do it, but of course there is some effort to it, which depends on the architecture of your current website.

If you're only, and really only, using JSPs in your current website, then you can just dump the JSPs into OpenCms, and that's it. Then you have the website within OpenCms, of course not yet editable, and then integrate the editable elements step by step, using structured content elements (XSDs). The process can't be described briefly in an answer here as it's quite complex, it definitely takes a bit of OpenCms experience to do it, as it's harder than building a OpenCms based website from scratch.

If your current application uses a framework like Spring, then there are additional steps to it. We've integrated Spring with OpenCms before and it works.

I assume most java CMS will allow what you need, but it will take a bit of effort in all of them. Additionally, if you're using jars in your current application, you need to check that there are no conflicts between those and those of the OpenCms version you're using.

Alternatively, you can just create your own small CMS functionality by implementing FCKEditor / CKEditor, if your CMS requirements are very basic.

Please provide some more details about your current technology stack / frameworks, etc. Then it's easier to answer in more detail.

Update (2015):

As of 2015, I meanwhile moved from OpenCms to Magnolia, and would recommend that very much. Documentation is great an they explicitly have a module for Spring integration named Blossom. https://documentation.magnolia-cms.com/display/DOCS/Blossom+module.