behavioral models for software development

© 2008 IBM Corporation

Behavioral Models for Software Development

Andrei Kirshin, Dolev Dotan, Alan Hartman

January 2008

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Haifa Research Lab – Model Driven Engineering Technologies Group


Abstract

MDD raising the level of abstraction, increasing the automation

Models and model transformations increased productivity, quality, effective way of adapting to changes in requirements

This talk focuses on models which describe the behavior of the system, and the tools for executing at the model level

Platform independent action language

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Outline

Introduction– Motivation

– UML Behavioral Modeling

– Action Language

UML Model Debugger– Debugging capabilities

– Debugging perspective

– Diagram animation

Testing– Model testing

– Model-based testing (test generation)

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Outline – Introduction



– Action Language






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Introduction – VisionTime

Developers

Variety & versatility of users: business analysts, architects, developers, testers

Tools

Many highly qualified developers

Abstraction

Registers,low level commands

Structures, operations, statements, expressions, classes, interfaces, packages

Components, services,features, behaviors,actions, patterns

3GL level debugging,3GL testing tools,

Assembler,Assembly debugger

CompilerRE

OO

DM

DD

PD

Few experts

PD – Procedural Development, RE – Reverse Engineering, MD – Model Discovery

Model level debugging Model level testingSupport for ALStatic model analysis

MDCode

Generation

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Behavioral Modeling Toolset

Traditional SoftwareDevelopment

Model DrivenDevelopment

CodeDebugger

ModelDebugger

CompilerModel

Transformation

IDEModeling

Tool

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MDD and Model Debugger

Identify defects at a much higher level of abstraction, earlier in the development cycle

Model Debugger

Transformation Execution

RuntimeExecutable ModelExecutable

Specification(e.g. code)

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Modeling with UML Structure

– Class (Class diagram)

– Component (Composite structure diagram) Behavior

– State machine (state machine diagram)

– Activity (activity diagram)

– Interaction (sequence/communication diagram)

– Action language (snippets of code in model)

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State Machines

Features include: Behaviors for: transition effects, state

entry, do, exit Composite states Nested state machines Concurrency (orthogonal states) Transition guards Conditionals (choice, junction)

Integration with the Object Oriented Model: Effect/entry/do/exit behaviors… Guards…

– …can access class attributes, call class operations, etc. Triggers:

– Operation calls

– Attribute changes

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Activity Diagrams – “Sophisticated Flowcharts”

Features include: Control flow Data flow Conditionals (choice node,

guards) Concurrency (fork & join) Nested behavior calls Data stores

Integration with the Object Oriented Model: (“Opaque”) actions – code snippets… Guard expressions…

– …can access class attributes, call class operations, etc.

Actions for:– Calling operations

– Reading and modifying attributes

– Sending signals

– and more…

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UML Behavioral Modeling

Structure: protocol, classes (capsules), ports and connectors

Behaviors (state machines, activities, interactions)– Stand-alone– Specify the implementation of operations– Specify the lifecycle of objects (capsules)– Specify state entry/do/exit behavior and transition effect

Code snippets (target language or platform independent)– Specify the implementation of operations– Specify state entry/do/exit behavior and transition effect– Activity actions– Guards (activity edge, state machine transition)

Flexible Very complex (almost as complex as code)

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Action Language

Snippets of Code in the Model

Target language (Java, C++, C#) or its subset Error prone, bound to specific target platform and compiler

Already known language Platform independent

New language to learn

Makes the model retargetable, less error prone

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Outline – UML Model Debugger



– Action Language






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Interactive Debugging

Traditional debugging– Running a main function

– Hitting a breakpoint

– Stepping

– Observing values

Interactive debugging (model “exerciser”)– Creating instances

– Invoking operations and behaviors, send signals

– Hitting a breakpoint

– Stepping

– Observing values

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Model Debugging Perspective

Debug Variables

Console

Diagram Animation

Signals

Event Pools

Instances

Breakpoints

I/O

Snippet

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Instances View

Dynamic debugging– Object creation and

destruction

– Method invocation

Create New Instance

Destroy Instance

Instance

Attribute

Double-click to Invoke

Operation

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Debug View

Control and display granularity – model elements– State, Transition, Action, Edge, etc.

Supports concurrency in behaviors – stack trace is a tree

Execution Stack

Step(into, over, out)

Stop Pause Resume

Send Signal Broadcast

Signal

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Variables View

Similar to Eclipse debugging framework view

Self Object

Behavior attributes, local variables and parameters

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Breakpoints View

Similar to Eclipse debugging framework view Breakpoints

– Statemachine: State, Transition, Entry, Do, Exit, Effect

– Activity: Action

“Do” Behavior

State

Transition

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Event Pools View

Shows pending events in event the pools of active objects

Pending Events

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Signals and I/O Views

Send and Broadcast Signal

Buttons

Double-click to send signal Signals

History

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Diagram Animation – State Machine

Current State

Execution Pending

Running Transition

Breakpoint

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Diagram Animation – Activity

Token Provider

Offer Path

Execution Pending

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Outline – Testing



– Action Language






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Debugging – Model Interpretation

Simulation / Emulation (for debugging and understanding) Recording of execution traces (assisted test generation)

Model Debugger

Test Generator

Test Execution Environment

UML Model Application

Test / Trace

Code Generation

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Debugging – Generated Code

Execution monitoring and control Execution trace animation Trace analysis results visualization

Model Debugger

Test Generator



Test / Trace

Code Generation

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Automatic Test Generation

Test is a sequence of stimuli and observations Model is used as the oracle to predict the expected results A bunch of tests is generated automatically according to provided criteria

Model Debugger

Test Generator



Test / Trace

Code Generation

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Test Editing

Manual test creation using model-level terms Editing of tests generated using the Test Generator or Model Debugger

traces

Model Debugger

Test Generator



Test / Trace

Code Generation

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Model Testing

Execution of tests on the model Used for model regression testing and test-first modeling approach

Model Debugger

Test Generator



Test / Trace

Code Generation

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Model Driven Testing of Applications

Execution of tests on the application Transformation to concrete test execution environment

Model Debugger

Test Generator



Test / Trace

Code Generation

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Testing Summary

Test creation– Manual (test editor)

– Assisted (execution trace recording)

– Automatic test generation

Model Testing– Execution of tests on the model

– Used for model regression testing and test-first modeling approach

Model-Based Testing of Systems– Transformation to concrete test execution environment

– Execution of tests on the application

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Summary

MDD is a practical option for improving SW production and capitalizing on existing SW assets through:

– Abstraction

– Automation

– Legacy modernization

UML Behavioral Modeling Action Language UML Model Debugger Model testing Model-based testing of applications

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References

IBM Haifa Research Lab – Model Driven Engineering Technologies group

http://www.research.ibm.com/haifa/dept/services/mdet.html Model Debugger

http://www.research.ibm.com/haifa/projects/software/ple/mex/index.html Model Grokking

http://www.research.ibm.com/haifa/projects/software/ple/grokking/index.html UML

http://www.uml.org/

Contacts:Andrei Kirshin, Dolev Dotan, Alan Hartman

{kirshin,dotan,hartman}@il.ibm.com

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