Using Event-Driven Process Chainsfor Model-Driven

Development of Business Applications

Daniel Lübke, Tim Lüecke,Kurt Schneider and Jorge Marx-Gómez

University Hannover, Software Engineeringdaniel.luebke@inf.uni-hannover.de

2Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

OutlineOutline

• Motivation

• Task Model Description

• Client/Server Interaction

• Example

• Conclusions & Outlook

3Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Distributed ERP ScenarioDistributed ERP Scenario

Enterprise (SME)

Clients

ApplicationServer

ServiceProvider

A

ServiceProvider

B

ServiceProvider

C

ServiceProvider

D

LocalData

Storage

4Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Being Flexible using Web Services?Being Flexible using Web Services?

• Web Service Composition is (comparably) easy:– Standard Languages (BPEL, YAWL, …)– Workflow Updates are easy to do– Functionality can flexibly composed out of services

• However:– The workflows have to be used!– User Interaction is required– User Interfaces are time-consuming to develop (, test and maintain

…)

• Therefore, this paper concentrates on the user interface

5Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Necessities for DevelopmentNecessities for Development

• SMEs are highly competitive due to their flexibility– Processes need to be as flexible

• That requires

– Inexpensive Changes• Otherwise process changes are too costly

– Easy changes• Not top-personnel

6Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Composition ArchitectureComposition Architecture

Task which needs user interaction

7Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Model Based User Interface GenerationModel Based User Interface Generation

• MB-UI has been a research field for many years– Often resulted in heavy-weight attempts– Breakthrough hindered by high effort compared to low advantages

– Light-weight approaches are more likely to succeed

• Common to most approaches: Task Model– Describes the activities a user can do– Like: edit, show, decide, …

8Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Task Model in EPCsTask Model in EPCs

• EPCs mainly consist of Events, Functions and Connectors

• Those are extended with markers representing common task model elements

Perform actionon order

Edit purchase order

Select productionp lant

C heck contract

∧ ∨

Contro l Edit Select User

W eb service reception

O rderreceived

synchronized splits

Add C ustom erW S

W eb service invocationInvocation Reception

9Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

User Interface GenerationUser Interface Generation

• Data Schema is represented using XML Schema

• Hierarchical structure of primitive and complex types

• Data to be shown or edited is decomposed via a matching editor hierarchy

10Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Client/Server-InteractionClient/Server-Interaction

CLIENT

CLIENT

SERVER

ProcessModel

Login

Handle Event

Retrieve EPC/TM

User

Interface

Evoke Event

ProcessUser

Interface End Subprocess

End Process

11Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

ExampleExample

Forward orderto productionW S

C heckprofit m arg in (PM )?

O rder R eceived

X

PM o.k.PM

too low

M anager decides

X

Approved R ejected

X

O rderforwared

M anager

PMtoo low

Approved R ejected

Makedecis ion

Editse lected

D ifferencevisua lized

V isua lized ifference

Edit PM

X

12Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

AdvantagesAdvantages

• Application Development– Our approach reduces development/maintenance efforts– Unified User Interfaces– On-the-fly generation

• Generation of UI-code– Code can be edited– Development efforts are reduced

• Prototyping– Interviews with Stakeholders

• Interactive Process/UI Feedback

– Prototype Applications/Feasibility Studies

13Daniel Lübke: Using EPCs for Model-Driven Development of Business Applications

Conclusions and OutlookConclusions and Outlook

• User Interface Generation can save much development effort– Allows easy changes of process and workflow models

• MB-UI extensions integrate seamlessly into EPCs– Standard EPC hierarchical refinement– Easy annotation– Few new elements

• Approach adaptable to other Models/UIs as well– BPEL, YAWL, …– Portlets, Web Applications, …

Thank you for your attention! Any questions?

Daniel Lübke <daniel.luebke@inf.uni-hannover.de>