By now, you are familiar with the built-in resource types in OpenCms: Page, Plain, Binary, Image, JSP, and XML template. These provide generic types that are often sufficient for running CMS applications. However, it is often desirable to have more specific definitions of content. In OpenCms, there are two ways of defining custom content formats.

The first is to extend the existing resource types to include your own definition. This integrates well with the existing user interface and back-end data structure, but it is limited to content that can be treated similarly to other OpenCms types.

The second method is to add a new content definition. The OpenCms content definition API provides hooks for serving external data through OpenCms. It provides a generic framework for dealing with data that cannot be expressed well within the OpenCms VFS. While it does not impose many of the limits of resource types, it is far more complex and does not integrate well with existing CMS tools...