JDave is a framework which provides an easy way to specify behavior of your classes. Key concepts are specification, which is a container for behaviors. Behaviors define the behavior of a class and they are always expressed within some context. Context defines the setting where particular behavior applies.

For example, we could specify a Stack by first identifying that it has (at least) three interesting states, an empty stack, a full stack and a stack which is neither empty nor full. We would then continue by specifying the behavior of a Stack when it is in these states. The behavior can then be expressed as:

Stack specification
Empty stack
- is empty
- is no longer empty after push
- ...
Full stack
- is full
- complains on push
- contains all items
- ...
Stack which is neither empty nor full
- adds to the top when pushing new item
- ...