Review Topics
The 3 Major Components of Workflow Management
Systems
1.
2.
3.
Buildtime
Metamodel
Runtime
1
Buildtime
• The buildtime component of workflow systems provides
the functions and capabilities to define, test, and manage
all workflow related information
• The buildtime component of workflow systems also
provides functions to manage and administer the workflow
system
2
Buildtime (Contd.)
• The buildtime of a workflow system usually manifests
itself in two different ways:
– Graphical User Interface (GUI)
• Business/workflow modeling tool
• All information is stored and managed in the WF system’ database
• The modeling tool operates either in the connected or disconnected
mode with the WF database
– Workflow Definition Language (WFDL)
• The language reflects the underlying structure of the meta model
• See page 67 of the text for a sample of WFDL
3
Buildtime (Contd.)
• Organizational data is usually stored in systems outside the
boundaries of a WFMS.
• Organizational data is periodically extracted into the
WFMS using batch processes
– Batch processes are generally used for import export function to
and from the WFMS respectively
– Online processes are used for CRUD like operations
• Soon as the process model goes into production, the
process model is frozen. The frozen state is called process
template
4
Buildtime (Contd.)
• No program interfaces directly with the database of the
WFMS
• The buildtime component manages the database of the
WFMS for all definitional data using an Application
Programming Interface (API)
• The API supports batch and interactive modes
5
Metamodel
• Metamodel provides the constructs and rules to model a
process, organization, or technology (program)
• It’s a model of a model
• It has many similarities with a data model, especially meta
data
6
Metamodel - Organization
• Lets take a look at the Organizational Metamodel
implemented by MQSeries Workflow on page 37
• WFMS can support:
– Fixed organizational model – relationships cannot be changed in
the metamodel
– Variable organizational model – relationships can be changed in
the metamodel, even a new metamodel can be created
• The underlying model to model the metamodel could be a
data model or an object model
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Metamodel - Organization
• The organizational data of a WFMS can be managed in
three different ways:
– WFMS manages all organizational data in its own database
– WFMS shares the data with other systems, and each of the systems
can modify the data
– WFMS only access the organizational data that is managed by
some other system
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Metamodel - Process
•
•
•
•
•
•
•
•
Control Connector – the arrow that defines the flow of control from
one activity to another activity.
Fork – the activity that is the source of parallel work
Join – the activity that is the target of the parallel work
Join Condition – whether the activity can be performed
Activation condition – when the activity can be carried out
Exit condition – when the activity has successfully completed
Input container – the data that is passed to the process or activity
Output container – the data that is returned by the process or activity
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Metamodel - Process
Assess
Risk
Collect Credit
Information
Accept
Risk
Customer #
# of people
requesting loan
Activity input
container
Risk rating
Activity output
container
Process input
container
Request
Approval
Reject
Risk
10
Metamodel - Process
• The are four general types of activities:
– Information activity – no implementation, e.g. call a customer
– Program activity – is implemented by a program, e.g. run the risk
assessment program
– Process activity – is implemented by another process, e.g. invoke
a sub-process
– Bundle activity – is implemented by bundling the multiple
instances of the activity using the planning (how many) and
processing (invokes the program/process) phases.
11
Metamodel - Program
• Focus on the process first
• When defining an activity, you may not know which
operating system the activity may be operating on
• You should be able to change the implementation without
changing the process model (late binding)
12
Metamodel - Program
Activity
Program
Properties
Common
Properties
WINNT
DLL
PATH D:\PROGRAMS\COLLINF.DLL
AIX
EXE
PATH D:\PROGRAMS\COLLINF.EXE
AIX
Windows NT
OS390
13
Metamodel - Program
Activity
OS
MQI
ORB
TPMon
Comm.
Program
Call
Message
Queuing
Method
Invocation
Transaction
Start
RPC
Invocation Mechanism
Program
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