BPMN 2.0 Analysts

Parallel Event-Based Gateway⌘

• All events must occur before a process can start

Complex Gateway⌘

• 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.

Data Modeling⌘

• Data modeling is used to describe physical or information items that are created, manipulated, and used during the execution of a Process.
• Data can be modeled using: Data Objects, Data Inputs, Data Outputs, Data Stores, Data Associations, ....

Data Objects⌘

• The primary construct for modeling data within the Process flow.
• Data Associations are used to move data between Data Objects.
• Tokens do not flow along a Data Association.

Data Input, Data Output⌘

• Activities and Processes often need data in order to execute.
• In addition they can produce data during or as a result of execution.
• Data requirements are captured as Data Inputs.
• Data that is produced is captured using Data Outputs.

Data Store⌘

• A DataStore provides a mechanism for Activities to get or update stored information that will persist beyond the scope of the Process.
• Represents a single unit of information (e.g. database record)

Link Events⌘

• 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).
• There can be multiple source Link Events, but there can only be one target Link Event.

Link Events Example ⌘

Link Events as Off-Page Connector⌘

Conditional Events ⌘

• Is triggered when a condition such as "Temperature above 20°C" become true.

Signal Events⌘

• A Signal is for general communication within and across Process levels, across Pools, and between Business Process Diagrams.
• A BPMN Signal is similar to a signal flare that shot into the sky for anyone who might be interested to notice and then react. Thus, there is a source of the Signal, but no specific intended target.

Signal Event Example 1⌘

Signal Event Example 2⌘

Error Events⌘

• 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.
• 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⌘

Error Events Example 2⌘

Error Events Example 3⌘

Error Event Exercises⌘

• Exercise 1.
• Exercise 2.

Escalation Events⌘

• 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⌘

Escalation Exercises⌘

• Exercise 1.

Compensation⌘

• 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
• A compensation handler performs the steps necessary to reverse the effects of an Activity.

Compensation handler⌘

• A compensation handler connected via a boundary Event can only perform “black-box” compensation of the original Activity.
• Compensation Activity is connected to the boundary Event through an Association.
• The Compensation Activity can be either a Task or a Sub-Process, has a marker to show that it is used for compensation only and is outside the normal flow of the Process.

Compensation Using Event Sub-Process⌘

A Compensation Event Sub-Process can access data that is part of its parent, and can recursively trigger compensation for Activities contained in its parent.

Compensation Exercises⌘

• Exercise 1.
• Exercise 2.

Transaction⌘

• 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⌘

Three basic outcomes of a Transaction:

• Succes
• Cancel
• Error

Collapsed Transaction Sub-Process⌘

Cancel Events⌘

• Cancel Events are only used in the context of modeling Transaction Sub-Processes
• Activities indicated by sequence flow from cancel event will be executed after transaction is rolled back

Transaction Exercises⌘

• Exercise 1.
• Exercise 2.

Loops and multi-instance⌘

Standard Loop ⌘

• 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 or 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⌘

Multi-Instance parallel

Multi-Instance sequential

• The instances MAY execute in parallel or MAY be sequential.
• Multi-Instance Activites are used with collection of items
• Multi-Instance Activity is similar to FOR EACH loop

Multi-Instance Activity Example⌘

Loop Exercises ⌘

Global Task and Global Process⌘

• A Global Task is a reusable, atomic Task definition that can be called from within any Process by a Call Activity.
• A Global Task is not defined within a Process, but is callable element.

• The types of Global Tasks are only a subset of standard Tasks types: GlobalUserTask, GlobalManualTask, GlobalScriptTask, and GlobalBusinessRuleTask
• A Global Process can be called from another Process.
  • Question: Do you know any example of non-global process?

Call Activity⌘

• A Call Activity is a type of Activity that identifies a point in the Process where a global Process or a Global Task is used.

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 ⌘

There are three basic types of BPMN Processes (Orchestrations):

• Private Non-executable (internal) Business Processes
• Private Executable (internal) Business Processes

• Public Processes

Collaboration⌘

• 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

Choreography⌘

• A Choreography defines the sequence of interactions between Participants (Pools).
• Choreographies exist outside of or in between Pools.
• Choreography does not exist in a single Pool. Each step in the Choreography involves two or more Participants.
• A Choreography does not have a central control mechanism.

Choreography Example 1⌘

Choreography Task⌘

• A Choreography Task is an atomic Activity in a Choreography Process.
• It represents an Interaction, which is one or two Message exchanges between two Participants.

Choreography Task with a Message⌘

Two-way Choreography Task⌘

Sequence Flow⌘

Gateways⌘

• Interactions between Participants can happen in sequence, in parallel, or through exclusive selection.
• Exclusive, Inclusive, Parallel, Event-based and Complex Gateways can be used with some constraints (because the lack of a central mechanism to maintain data visibility, and no central evaluation)

Exclusive Gateway Example⌘

Choreography Example 2 from spec⌘

Business Process Model and Notation (BPMN), Version 2.0, pages 318-319

Choreography Example 2 from spec⌘

Conversations⌘

• 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⌘

Annex⌘

BPMN shapes⌘

• Table 7.1 - Basic Modeling Elements (BPMN 2.0 Specification)
• Table 7.2 - BPMN Extended Modeling Elements (BPMN 2.0 Specification)
• BPMN 2.0 poster - http://www.bpmb.de/images/BPMN2_0_Poster_EN.pdf

BPMN tools⌘

• Signavio Process Manager - http://www.signavio.com/
• Camunda Modeler - https://camunda.com/products/modeler/
• Bizagi Modeler (desktop) - http://www.bizagi.com/en/bpm-suite/bpm-products/modeler
• Intalio|bpms Community Edition (desktop) - http://bpms.intalio.com/
• jBPM - http://www.jbpm.org/
• Activiti - http://activiti.org/
• Bonita BPM (desktop) - http://www.bonitasoft.com/
• Yaoqiang BPMN Editor (desktop) - http://sourceforge.net/projects/bpmn/

BPMN types of events

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