Transcript poosd-11.ppt

Principles of Object-Oriented
Software Development
Business Process Redesign
Business Process Redesign
Introduction
Business Objects -- The San Francisco Framework
Business Process Modeling
Object-Oriented Simulation
Visualization support
Migrating from legacy systems
Summary
Q/A
Literature
Literature
Business Process Redesign
• business objects -- The San Francisco
Framework
• business process modeling -- simulation
• visualization support -- collaboration and
decision making
• migrating from legacy applications -business objects
Additional keywords and phrases:
business objects, business logistics, frameworks, object-oriented
simulation
Business Objects
San Francisco Framework
Business Objects
access to (relational) data
Designer -- define data model
universes, classes, objects -- shield from tables
Business User -- deploy views
select, order, summarize, aggregate, tabulate
The San Francisco
Framework
(Business) Frameworks
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collection of components
generic solution for a class of problems
frame of mind for solving problems
set of architectural constraints
The San Francisco Framework
Core Business Processes
Accounts Receivable/Payable
General Ledger Framework
Sales Order Management Framework
Purchase Order management Framework
Common Business Objects
Business Partner, Address, Number, Currency
Foundation Object Model Classes
Command, Entity, Dependent, Collection/Iterator, Factory
San Francisco Object Layers
Refining Quality Control
Business Process Modeling
Subsections:
Logistics-based modeling
Business process simulation
Example -- requests for loans
Logistics-based modeling
criteria for redesign
• the time spent in executing a business
process
Product lead time
time between order and delivery
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processing time -- actual working time
queue time -- waiting for a resource
setup time -- for the job to get started
wait time -- waiting for a job to complete
transport time -- between resources or
operations
Logistics-based business models
Logistics-based modeling
primitives
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operation -- processing component
task -- a series of consecutive operations
transport -- transport of information
choice -- affects flow of information
organizational units -- to represent
departmental boundaries
• external agents -- opaque entities
• archives -- paper-based storage facilities
Business Process Simulation
• data -- which represents the product or case,
i.e. the
• information, that flows through the process.
• datahandler -- which is the basis for all
classes that handle information.
Derived from datahandler class:
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operation -- executed by employee
transport -- connects datahandlers
waitqueue -- wait for processing
choice -- to model alternatives
archive -- for storage of resources
external agent -- blackbox entity
Example -- requests for loans
Processing alternatives
Current Situation:
Our first model, slide models (left), which represents the current
situation, consists of a client producing, for example requests for a
loan at a bank. The requests are initially handled by a clerk whose
task is to send requests for amounts greater than 10000 dollars to
the boss. The boss, whose task is to approve or deny the loan, sends
the result back to the clerk for processing. If the amount is less than
10000 dollars, the clerk has authority to process the request himself.
Redesign Alternative: In our second model, slide models(right),
which is the result of a redesign effort, requests are handled by a
clerk who enters the data into a computer. The computer now makes
the decision as to whether the loan is approved - for loans of value
less than and greater than 10000 dollars. The clerk then passes the
results on to another clerk for the task of dispatching loans.
Presenting a Redesign Alternative
histogram leadtimes
agent client generate leadtimes
client -duration 60 poisson
transport t1
t1 -duration 20
employee clerk
operation receive clerk
receive -duration 20.0 5.0 normal
The script
Object-Oriented Simulation
The SIM library
Simulation classes
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simulation -- the scheduler
event -- representing the events
entity -- process consisting of events
generator -- random distributions
resource -- to model passive objects
queue -- to hold waiting events
histogram -- to plot the results
analysis -- for statistical analyses
State diagram for event
Event states
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passive - currently not available for any processing
active - this is the event currently being processed
queued - the event is in a queue
pending - the event is in the scheduler
conditional - the event is on the conditional list
closed - on the conditional list but unavailable
Example -- dining philosophers
Visualization support
Subsections:
Interactive Information Visualization
DIVA -- distributed visualization architecture
Retail USA -- (c) 1995-1999 Visible Decisions Inc
So many users, so many
perspectives
In3D Architecture
Interaction -- visualization
• selection -- clicking a view -> action
• brushing -- display detailed information
• controllers -- sliders and buttons for
manipulation
• filtering -- apply constraints on the data
• sensors -- triggered by user navigation
• navigation -- move around and explore
• commands -- user-defined macros
DIVA - distributed
visualisation architecture
Conceptual architecture (DIVA)
DIVA is based on three requirements
• to allow for multiple views or perspectives,
according to the users' information needs;
• to provide adaptive visualizations, allowing
for experimentation; and
• to support a networked, Web-based
infrastructure.
Screenshot
Collaborative visualization
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sessions -- meetings/roles
roles -- chair, listener, talker, interactor
interactor -- dispruptive or non-disruptive
perspectives -- sharing and enforcing
communication -- telepointers, chatting, ...
Architecture DIVA -- display agents
Migrating from legacy
applications
Three tier architecture
Summary
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Business Objects -- San Francisco
Framework
• business objects -- access to relational data
• framework -- collection of components
• generic solution for a class of problems -frame of mind
• architectural constraints -- Java, Web-aware
applications
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Business Process Modeling
• logistics-based modeling
• business process simulation
• example -- requests for loans
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Object-Oriented Simulation
• simulation classes -- event, entity, generator,
resource, queue
• event scheduling strategy -- conditional,
passive, pending
• dining philosophers -- events versus
processes
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Visualization support
• So many users, so many perspectives
• DIVA -- distributed visualization
architecture
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Migrating from legacy
applications
• fat versus thin clients -- screen scraping
• Web-aware applications -- wrapping the
legacy
Questions
1. Why would you need business objects? Discuss this from the
perspective of the end-user as well as from the perspective of
management.
2. What are the motivations underlying the San Francisco framework?
3. Give an overview of the component layers constituting the San
Francisco framework.
4. Explain the goals of logistics-based business modeling. Discuss
possible means to support business modeling.
5. Give an example of business process simulation.
6. What classes can you think of for a library supporting object-oriented
simulation?
7. What are the requirements for visualization support? Can you think of
actual classes?
8. Discuss the issues that may arise in migrating from legacy
applications? What possible solutions can you think of?
Further reading
For more information on business process redesign, consult
[Davenport90], [Hammer90] and [Wastell94]. For an in depth
treatment of simulation, you may read for example [Watkins93].