1 Static Analysis of Business Artifact-centric Operational Models Presented by Cagdas Gerede Cagdas Gerede 1, Kamal Bhattacharya 2, Jianwen Su 1 1: University.

1

Static Analysis of Business

Artifact-centric Operational

Models

Presented by Cagdas Gerede

Cagdas Gerede1, Kamal Bhattacharya2, Jianwen Su1

1: University of California Santa Barbara2: IBM T.J. Watson Research Center

2

Typical Approaches for Business Process Modeling

Characteristics:[Leymann99, Aalst-JCSC98, Jackson97,Morrison94] Process-centric: Focus on control and coordination of tasks Ignore the informational perspective or treat it only

within the context of single activities Case-driven and cases are logically independent

Problems Lack of flexibility

[Wang,Kumar-BPM05], [Aalst et al-DKE05], …

Hard to deal with changes[Casati et al-ER96], [Aalst et al-CSSE00], [Weske et al-HICSS01], …

Integration efforts are hindered [Bhattacharya-07]

3

Artifact-centric Business Process Modeling Developed by IBM Research

[NigamCaswell-IBMSJ03], [Bhattacharya et al-BPM07], [Liu et al- CAiSE07]…

Centered on Business Artifacts: data objects that capture key information pertinent to business context

Focus on life-cycles of business artifacts

Similarities with data flow diagramming [DeMarco78], flow-based programming [Morrison94]

Applied in practice successfullyInsurance, Manufacturing, Pharmaceutical Industries

[Bhattacharya et al - IBMSJ05]

4

Example: High Tech Restaurant

Guest Check

Artifacts

Kitchen Order

Receipt

Cash BalancePending

Active

Payment Completed

Canceled

Guest CheckcustomerNametableNopaymentDate…

data

states

5

Example: High Tech Restaurant

Guest Check

Artifacts

Kitchen Order

Receipt

Cash Balance

OpenGCs

ArchivedKOs

ClosedGCs

ArchivedGCs

PendingReceipts

ArchivedReceipts

Cash Balance

PendingKOs

PaidReceipts

DisagreedReceipts

ReadyKOs

Add Item

Deliver

Prepare &Test Quality

Create Guest Check

6

PrepareReceipt

Example: High Tech Restaurant

Guest Check

Artifacts

Kitchen Order

Receipt

Cash Balance

OpenGCs

ArchivedKOs

ClosedGCs

ArchivedGCs

PendingReceipts

ArchivedReceipts

Cash Balance

PendingKOs

PaidReceipts

DisagreedReceipts

ReadyKOs

Add Item

Deliver

Prepare &Test Quality

Create Guest Check

GC KO

UpdateCash Balance

Payment

RecalculateReceipt

RC

CB

7

Example: High Tech Restaurant

OpenGCs

Add ItemGC

KO

KO

KO

KO

Deliver

GC

ArchivedKOs

PrepareReceipt

ClosedGCs

ArchivedGCs

PendingReceipts

GC

RCGC

UpdateCash Balance

Payment

RecalculateReceipt

RC

RC

ArchivedReceipts

Cash Balance

GC

CB

RC

RCGC

KO

Prepare &Test Quality

PendingKOs

Create Guest Check

PaidReceipts

RC

DisagreedReceipts

RC

RC

GC

ReadyKOs

KO

9

Location Uniqueness: An artifact should appear only in one location

Persistence: An artifact should never be lost

Arrival: Can an artifact arrive into a repository?

Revisit: life cycle properties

Paid Receipts

Disagreed Receipts

Receipt ReceiptPaid Receipts

Disagreed Receipts

or

Open GuestChecks

Archived Guest ChecksGuest Check

10

Related Work Emphasis on Data Design as well as Control Flow Design

Document Driven Workflow Systems [Wang,Kumar-BPM05] Case Handling [Aalst et al-DKE05] Vortex [Hull et al-WACC99], [Fu et al-TACAS01] INSYDE [King,McLeod-TOIS85], TAXIS[Mylopoulos et al-

TODS80], …

Constraints on Life-cycles of Objects Object Migration [Su-TCS97] Object Histories [Ginsburg,Tanaka-TODS86] Object Constraint Language …

11

Remainder of the TalkFormalization of Artifact-centric Business Process

ModelsArtifactsTasksOperational Models

Analysis of PropertiesLocation UniquenessPersistenceArrival

Conclusions

12

Artifact An artifact

attributes, methods, states

Similar to object-oriented classes augmented with states Typestate [StromYemini-TSE86] Method schemas

[Abiteboul et al–PODS90] Method structures

[Hull et al–FODO88] UML OCL, Alloy [Jackson-TOSEM02]

Pending

Active

Payment Completed

Canceled

Guest Check

addOrder

setCancelDa

te

receiptRequest

setPaymentDate

addOrder(…)setPaymentDate(…)

customerNametableNopaymentDate

ReceiptOrder

data

references

methods

states

OpenGCs

Create Guest Check

GC

13

Task A task describes the actions performed

on artifacts has a set of variables has a guarded state machine

Artifact creationArtifact check out / check in Read/Update artifact data via

artifact methodsRead from external environment

R1.checkOut(order)

read(approvedDate)

order.setApproved(approvedDate)

R2.checkIn(order)

reset

R1Pending Orders

R2Live Orders

LiveOrders

ApproveKO

KO

14

Operational Model

Operational Model O = (A, R, T)A: set of artifact typesR: set of repositoriesT: set of task types

Open

GCs

Add ItemGC

KO

KO

KO

KO

Deliver

GC

Archived

KOs

Prepare

Receipt

Closed

GCs

Archived

GCs

Pending

Receipts

GC

RCGC

Update

Cash Balance

Payment

Recalculate

Receipt

RC

RC

Archived

Receipts

Cash

Balance

GC

CB

RC

RCGC

KO

Prepare &

Test Quality

Pending

KOs

Create

Guest Check

Paid

Receipts

RC

Disagreed

Receipts

RC

RC

GC

Ready

KOs

KO

15

Semantics Configuration

A configuration is derivable from another configuration if …

Execution graph of an operational model and a root configuration is a Kripke structure

18

Location Uniqueness, PersistenceFormalism guarantees location uniqueness and

persistence

Location Uniqueness:Artifact cannot be

checked out by two taskschecked in two repositoriesduplicated

PersistenceAn artifact can not be

deletedoverwritten

19

Checking Arrival

Reachability on execution graph

Open GuestChecks

…

Archived GuestChecks

…

Ci

……

C1

C2 C3

C4…… …

Example: Does a guest check arrive at the archived guest checks repository?

20

Arrival is not decidable

Theorem: It is not decidable to check if an artifact can

arrive into a repository R for an operational model O and

a root configuration of O.

But …

21

without Artifact Creation?Observation

Size of execution graph: InfiniteDomains are infiniteTasks can read values from infinite domains

Finite abstraction of infinite spaceDefine an equivalence relation among configurations

(similar to region approach [Alur-99])

22

Abstraction Example:

- only constant appears in the specification is 10- two scalar variables: cost, amount

amount

cost

11

5

12

5

13

5

14

5…

cost < 10 < amount

4

5

Equivalence class:

11

5

4

5

Abstraction

23

Decidable Fragment

Theorem: It is decidable to check if an artifact can arrive into a

repository R for an operational model O without new artifact

creation, and a root configuration of O.

24

ConclusionsPreliminary results on life cycle properties of

business artifacts

Many interesting questions:More declarative model

Automatic Towards Formal Analysis of Artifact-Centric Business Process Models [Bhattacharya et. al. BPM 2007]

A language for specifying artifact life-cycle propertiesSpecification and Verification of Artifact Behaviors in Business

Process Models [Gerede-07]

Multi-artifact interactionsAutomated design and toolsEvolution of models (business rules)

25

Questions and Comments

Thanks