Difference between command, form, business, and entity objects in Spring terms?
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I'm trying to wrap my head around the differences between these objects in terms of loosely coupled systems.  Is a business object the same as an entity object?  Can I use a business or entity object in MVC as my command object?  Is command object the same as a form object? Just looking for a clarification of the types of objects in Spring terms and usage.

I found a few questions on stackoverflow, but nothing that explained it to my liking.

Spring Web MVC docs seem to say you can use your business (entity?) objects as your command/form objects, but wouldn't this go against separation of concerns?

From the Spring Docs:

> Reusable business code, no need for duplication. Use existing business objects as command or form objects instead of mirroring them to extend a particular framework base class.