Filip Stachecki at 12:46, 4 March 2014

2014-03-04T12:46:43Z

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[[Category:Razvan|Z01]]

==Parallel Event-Based Gateway⌘==

[[File:ParallelEventBasedGateway.png]]
*All events must occur before a process can start

[[File:ParallelEventBasedGatewayExample.png]]

==Complex Gateway⌘==

[[File:ComplexGateway.png]]
*The Complex Gateway can be used to model complex synchronization behavior
* For example, it could specify that tokens on three out of five incoming Sequence Flows are needed to activate the Gateway.

[[File:ComplexGatewayExample.png|400px]]

==Link Events⌘==
[[File:LinkEvents.png]]

* A Link is a mechanism for connecting two sections of a Process.
* Link Events can be used to avoid long Sequence Flow lines.
* The use of Link Events is limited to a single Process level (i.e., they cannot link a parent Process with a Sub-Process or one pool to another pool).

[[File:LinkEventsExample.png]]

==Error Events⌘==

[[File:ErrorEvents.png]]
* An Error is generated when there is a critical problem in the processing of an Activity or when the execution of an Operation failed
*An '''Error''' indicates that a named Error should be generated.
*3 types of error events:
**Start '''Event Sub-Process''' Interrupting
**Intermediate '''Boundary''' Interrupting
**End
* Process can't wait for an error or rise an error in itermediate event (only in Boundary Intermediate)
* Process can't be instantiated using error event (only in Event Sub-Process)
===Error Events Example 1⌘===

[[File:BasicExceptionHandling.png]]
[[File:Ex02_BasicExceptionHandlingMerge.png]]
===Error Events Example 2⌘===

[[File:Ex03_ExceptionHandling.png]]
===Error Events Example 3⌘===
[[File:Ex04_ExceptionHandling.png]]
===Error Event Exercises⌘===

==Escalation Events⌘==

[[File:EscalationEvents.png]]
* An Escalation identifies a business situation that a Process might need to react to.
*In contrast to an Error, an Escalation by default is assumed to not abort the Activity to which the boundary Event is attached.

===Escalation Example⌘===
[[File:Escalation.png]]

===Escalation Example 2⌘===
[[File:Escalation2ndVersion.png]]

===Escalation Exercises⌘===

==Compensation⌘==
[[File:Compensation.png]]
* Compensation is '''undoing steps''' that were '''already successfully completed''', because their results and possibly side effects are no longer desired and need to be reversed.
* If an Activity is still active, it cannot be compensated, but rather needs to be canceled.
* Compensation is not an error handling
===Compensation Example⌘===
[[File:CompensationExample.png]]
===Compensation Exercises⌘===

==Transaction⌘==
[[File:Transaction.png]]
* Is a specialized type of Sub-Process that will have a special behavior that is controlled through a transaction protocol.
* Transaction verifies if all of the participants have successfully completed their end of the transaction or have been restored to the equivalent of their original state.
* ACID model describes transactions:
**'''Atomic''' - transaction is '''"all or nothing"''': if one part of the transaction fails, the entire transaction fails, and the system state is left unchanged.
**'''Consistent''' - any transaction will bring the system from one valid state to another.
**'''Isolatated''' - concurrent execution of transactions results in a system state that would be obtained if transactions were executed serially, i.e. one after the other.
**'''Durable''' - once a transaction has been committed, it will remain so, even in the event of power loss, crashes, or errors.
===Transaction in BPMN⌘===
[[File:TransactionOutcomes.png]]

Three basic outcomes of a Transaction:
* Succes
* Cancel
* Error

===Cancel Events⌘===
[[File:TransactionCancel.png]]
* Cancel Events are only used in the context of modeling Transaction Sub-Processes
* Activities indicated by sequence flow from error event will be executed after transaction is rolled back

===Transaction Exercises⌘===

==Loops and multi-instance⌘==
=== Standard Loop ⌘===
[[File:LoopingActivity.png]]
*The Activity will loop as long as the boolean ''loopCondition'' is true
*The condition is evaluated for every loop iteration, and MAY be evaluated at the beginning or at the end of the iteration (''testBefore'' = true lub ''testBefore'' = false)
*In addition, a numeric cap can be optionally specified - ''loopMaximum''
*Loop activity instances are sequentially executed - one after another.
*Loop Activity is similar to DO WHILE loop.

=== Multi-Instance Activity⌘===

[[File:Element_multiple_instances_parallel.png|100px]] [[File:Figure10-48-activity-multi-instance-marker-for-parallel-instances.png|100px]] Multi-Instance parallel

[[File:Element_multiple_instances_sequential.png|100px]] [[File:Figure10-49-activity-multi-instance-marker-for-sequential-instances.png|100px]] Multi-Instance sequential
*The instances MAY execute in '''parallel''' or MAY be '''sequential'''.
*Multi-Instance Activities are used with collection of items
*Multi-Instance Activity is similar to FOR EACH loop

===Multi-Instance Activity Example⌘===

[[File:MultiInstanceActivityExample.png|400px]]

=== Loop Exercises ⌘===

[[File:LoopExercise1.png]]

==Process, Collaboration, Choreography and Conversation in BPMN 2.0⌘==
=== Process - again⌘===

A Process describes a sequence or flow of Activities
in an organization with the objective of carrying out work.

*'''Process''' is depicted as a graph of Flow Elements, which are a set of Activities, Events, Gateways, and Sequence Flows that define finite execution semantics.
* BPMN uses the term Process specifically to mean a set of flow elements
* It uses the terms '''Collaboration''' and '''Choreography''' when modeling the interaction between Processes

==== Types of BPMN Processes ⌘====

[[File:FIgure7-1-example-of-a-private-business-process.png|500px]]

[[File:Figure7-2-example-of-a-public-process.png|500px]]

* There are three basic types of BPMN Processes:
*# Private Non-executable (internal) Business Processes
*# Private Executable (internal) Business Processes
*# Public Processes

===Collaboration⌘===
[[File:Figure7-6-example-of-collaboration-diagram-with-black-box-pools.png|300px]]
* Collaboration is a collection of Participants shown as Pools, their interactions as shown by Message Flows, and MAY include Processes within the Pools and/or Choreographies between the Pools
* A Choreography is an extended type of Collaboration

====Collaboration Example⌘====
[[File:Figure7-3-example-of-collaborative-process.png|400px]]

===Choreography⌘===

[[File:CollaborationChoreography.png|200px]]
[[File:SimpleChoreography.png|200px]]

* Choreography looks like Private Business Process
* Choreography formalizes the way business Participants coordinate their interactions.
* The focus is not on orchestrations of the work performed within these Participants, but rather on the exchange of information (Messages) between these Participants.

====Choreography Example 1⌘====

[[File:Choreography.png]]

====Choreography Example 2 from spec⌘====
Business Process Model and Notation (BPMN), Version 2.0, pages 318-319

[[File:ChoreographySpecExample1.png|200px]]
[[File:ChoreographySpecExample2.png|200px]]

===Conversations⌘===
[[File:SimpleConversation.png|400px]]
*The Conversation diagram is particular usage of a Collaboration diagram (simplified version of Collaboration)
*Pools usually are empty.
*A Conversation is a logical grouping of Message exchanges
====Conversation Example⌘====
[[File:Conversation.png]]

=Annex=
Business Process Model and Notation, v2.0, page 261

[[File:TypesOfEvents.png]]

{{BPMN Links}}
{{BPMN Links PL}}

BPMN 2.0 Analysts Razvan - Revision history

Filip Stachecki at 12:46, 4 March 2014