Outline

Introduction Problem Statement Object-Oriented Design Aspect-Oriented Design Conclusion Demo

Introduction

Project: UML Class Diagram Drawing Complex Issue

Project Objective Practice Aspect Oriented Design &

Development No problem with Rational! ;)

Problem Statement Complex nature of Software Design Notation

UML Develop a UML Design Tool Implement using Aspect

Technology

Requirements Analysis Create Class Structures Present the Structure

Logical View Diagram View

Support Basic UML Elements Export Images Print Images

User Interface Prototype

Use Cases

Create Model

Manipulate Model

Close Model

Save Model

Load Model

Print Diagram Export Diagram Image

User

Use Cases

Add Diagram

Manipulate Diagram

Delete Diagram

Add Model Element

Delete Model Element

Manipulate Model Element

User

Add Class

Add Interface

<<extend>>

<<extend>>

Add Stereotype

<<extend>>

Add Package

<<extend>>

Object-Oriented Design Logical Model Diagram Model Views Tools Managers

TreeViewManager DiagramViewManager

Logical Model Composite Pattern

Association(from data)

ClassElement(from data)

InterfaceElement(from data)

Package(from data)

Inheritance(from data)

Dependency(from data)

Aggregation(from data)

UMLModelModelElement

(from data)1..n1 1..n1

Managers - Singleton Pattern

public class Manager {

private static Manager instance = null;

private Manager() { }

public static Manager getInstance() { if (instance == null) { instance = new Manager(); }

return instance; }}

Other Design Patterns Factory Method

Creating diagram element UIs Observer

Reflecting data model updates to views

Faćade Saving, loading Project Drawing diagram contents

Crosscutting Concerns (Aspects)

View Update Product Version Generation

View Updating Update of views due to model change

Tool<<Interface>>

AssociationTool

handleMouseMove()handleMousePress()handleMouseRelease()

NodeTool

handleMouseMove()handleMousePress()handleMouseRelease()

SelectionTool

handleMouseMove()handleMousePress()handleMouseRelease()

View Updating

CrosscuttingConcern

DiagramEditor

repaint()

View Updating

TanglingCode

ScatteredConcern

class NodeTool { void handleMouseMove() { ... DiagramViewManager.getInstance().

getCurrentDiagramEditor().repaint(); }}

class AssociationTool { void handleMouseMove() { ... DiagramViewManager.getInstance().

getCurrentDiagramEditor().repaint(); }}

Aspect Code View Updateaspect ViewUpdating {

}

Aspect Code View Updateaspect ViewUpdating {

pointcut updatesView(): call(* tool.*.*(..));

}

Aspect Code View Updateaspect ViewUpdating {

pointcut updatesView(): call(* tool.*.*(..));

after(): updatesView() { DiagramViewManager.getInstance().

getCurrentDiagramEditor().repaint(); }}

View Updating using AOP Crosscutting is localized

No scattering No tangling Increased modularity

Aspect Code

Base Code

Changes can be easily handled Scenario:

Interface of “DiagramEditor” has changed

Solution: Just need to change the “advice”

code

after(): updatesView() { DiagramViewManager.getInstance(). getCurrentDiagramEditor().repaint(); }

after(): updatesView() { DiagramViewManager.getInstance(). getCurrentDiagramEditor().invalidate(); }

Product Version Generation Different Versions

Personal Standard Enterprise

How to develop? Different Source

Trees

Enterprise EditionSource

Personal EditionSource

Standard EditionSource

Changes areunmanageable

Product Version Generation Different Versions

Personal Standard Enterprise

How to develop? Different Source

Trees Inline checking

public void printDiagram() {

int version = getVersion(); if ( version == ENTERPRISE ) { ... } else if ( version() ==

STANDARD ) { ... } else { ... }

} ScatteredConcern

TanglingCode

Product Version Generation Different Versions

Personal Standard Enterprise

How to develop? Different Source

Trees Inline checking Aspects

Aspect Code Version Controlaspect VersionControlling {

}

Aspect Code Version Controlaspect VersionControlling {

pointcut enterpriseOps(): call(* MainFrame.printDiagram()) || call(* MainFrame.exportDiagram());

}

Aspect Code Version Controlaspect VersionControlling {

pointcut enterpriseOps(): call(* MainFrame.printDiagram()) || call(* MainFrame.exportDiagram());

around(): enterpriseOps() { JOptionPane.showMessageDialog(null,

"This operation is supported in Enterprise Edition.","Warning", JOptionPane.WARNING_MESSAGE);

}

}

Product Version Generation using AOP Crosscutting is localized

No scattering No tangling Increased modularity

Aspect Code

Base Code

Changes can be easily handled Scenario:

Change supported operations in versions

Solution: Just need to change the “pointcut”

pointcut enterpriseOps(): call(* MainFrame.printDiagram()) || call(* MainFrame.exportDiagram());

pointcut enterpriseOps(): call(* MainFrame.layoutDiagram());

Aspect Oriented Design Simple, easy to understand design Aspect notation

UML extension mechanism (stereotypes)

VersionControlling

<<pointcut>> enterpriseOps()

<<aspect>>ViewUpdating

<<pointcut>> updatesView()

<<aspect>>

Aspect Specification Using Composition Filters Version Control

versionControl: Error = {

enterpriseEdition => {printDiagram, exportDiagram}, standardEdition ~> {printDiagram, exportDiagram} };

Conclusion Complex Software Systems Several concerns were crosscut

Not easy to localize, scattering, tangling Reduces modularity

We have overcame these using AOP Design became more modular Changes became more manageable

Demo

Thank You! Questions?