Answer by Flavio Sadeghi

Flavio Sadeghi — Fri, 30 Dec 2016 12:55:25 -0500

First we have to separate between configuration and runtime data:

Configuration data are in the system database stored data, like Applications, Cases, Tasks, Users, etc.
Runtime data are not persistent and exists only at runtime, like the requests or sessions.

All API calls on the Ivy-Bean returns either configuration or runtime data related to the current execution context. E.g. the current executing request or the task of the current execution process.

The following APIs return runtime objects:

Ivy.request() Returns the current execution IProcessModelVersionRequest
Ivy.session() Returns the related IWorkflowSession to the current request

The following APIs return configuration objects:

Ivy.wf() Returns the IWorkflowContext of the current execution Application.
Ivy.wfTask() Returns the ITask of the current process
Ivy.wfCase() Returns the ICase of the current process

Further calls on a configuration object returns always further configuration objects:

ITask.getCase() Returns the ICase the ITask belongs to
ICase.getProcessModelVersion() Returns the IProcessModelVersion the ICase belongs to
ITask.getProcessModelVersion() Is equivalent to ITask.getCase().getProcessModelVersion()
ITask.getProcessModel() is quivalent to ITask.getCase().getProcessModelVersion().getProcessModel(). Basically each ITask belongs to a ICase, ICase belongs to a IProcessModelVersion, A PMV belongs to a IProcessModel and PM belongs to a IApplication. So the following two API calls are equicalent
Ivy.wfCase().getApplication().getProcessModels() returns all Process Models of the Application the current Case belongs to. As well as the call Ivy.wfTask().getApplication().getProcessModels(). Because a task and a case belongs to the same pmv, pm and application.
IProcessModelVersionRequest.getProcessModelVersion() Returns the IProcessModelVersion the IProcessModelVersionRequest belongs to
Ivy.request().getProcessModel().getReleasedProcessModelVersion(): The current IProcessModelVersionRequestbelongs to a Process Model, this process Model has one single ‘released’ Process Model Version. This is returned here and this has not to be the same as ivy.request.getProcessModelVersion(), because a Case/Task lives always in the PMV the Case was started in. Etc.

Hope this information will help. Don't hesitate to ask further question as comment. I will update the answer.

Answers to: Differences of public api

Answer by Flavio Sadeghi