Understanding the role of validation calls in real business applications

In business integration of Diagrammer, it is obvious that any diagramming operation is generally interpreted as an operation in the application data model or in the logical workflow in the application :

The context of Diagrammer integration can be different from an application to another. In order to make the visualizer more flexible, like adapting default interactions to the functional specifications, some diagramming operations are made controllable at prior and posterior times in a flexible way. The control is made at some Action classes via several parameters in order to block or enable some operations and to validate them. Among these operation constraints:

Generally, a validation process can be done:

The validation process is handled by the request manager in Diagrammer. All validation needs must be described by registering requests for each operation in that manager. see "Configuring Requests" section