Technology Tutorial

Software Engineering 2

(02162)

- Details and Advanced Concepts -

Patrick Könemann (pk@imm.dtu.dk)

Oct 19th 2009

2

Previous Tutorials.

1. A view and a selection listener for file types

public void createPartControl(Composite parent) {

viewer = new TableViewer(parent, SWT.MULTI | SWT.H_SCROLL | SWT.V_SCROLL);

viewer.setContentProvider(new ArrayContentProvider());

viewer.setLabelProvider(new LabelProvider());

getSite().getPage().addSelectionListener(this);

}

@Override

public void selectionChanged(IWorkbenchPart part, ISelection selection) {

List<String> list = new ArrayList<String>();

if (selection instanceof StructuredSelection) {

StructuredSelection str = (StructuredSelection) selection;

if (!str.isEmpty()) {

for (Object obj : str.toList()) {

if (obj instanceof IResource) {

IResource resource = (IResource) obj;

list.add(resource.getName() + " (type: " + resource.getFileExtension() +

", path: " + resource.getFullPath().toString() + ")");

}

}

}

}

viewer.setInput(list);

}

3

Previous Tutorials..

1. A view and a selection listener for file types

2. Create an EMF model (for Petrinets), generate code, and install a

command (for simulation) as a popup action for transitions

4

Previous Tutorials…

1. A view and a selection listener for file types

2. Create an EMF model (for Petrinets), generate code, and install a

command (for simulation) as a popup action for transitions

3. Create a compound command for creating an object and set its initial id

5

Previous Tutorials….

1. A view and a selection listener for file types

2. Create an EMF model (for Petrinets), generate code, and install a

command (for simulation) as a popup action for transitions

3. Create a compound command for creating an object and set its initial id

4. Use GMF to generate a graphical

editor for Petrinets and install

a command (for simulation) as a

popup action for transition figures

6

Previous Tutorials…..

1. A view and a selection listener for file types

2. Create an EMF model (for Petrinets), generate code, and install a

command (for simulation) as a popup action for transitions

3. Create a compound command for creating an object and set its initial id

4. Use GMF to generate a graphical

editor for Petrinets and install

a command (for simulation) as a

popup action for transition figures

5. A simple dashboard view for

Petrinets with listeners/adapters

showing the current number of

tokens on selected places

7

Motivation

This lecture covers advanced topics after the regular tutorials.

But didn’t we get enough tutorials

yet?!

These were just the basics.

The following advanced concepts probably save a lot of time later.

Then why listening now?!

We can read things later in the slides!

Good, do that!

But following now will help you understand things much better.

And not everything I say is in the slides ;-)

8

Overview

Topic Concepts Examples Slides

Resources in

Eclipse

Dialogs

OCL in EMF / GMF

GMF:

Graphical properties

in the model

GMF: Architecture

GMF: Decorator

9

Resources in Eclipse: Examples

C:\se2\workspace\

.metadata\

dk.dtu.imm.se2.petrinet\

model\

petrinet.ecore

petrinet.genmodel

src\

…

bin\

…

META-INF\

MANIFEST.MF

.project

plugin.xml

Images are also stored as IFiles ;-)

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

java.io.File

IWorkspace

(metadata directory)

IProject

IFolder

IFile

IFile

IFolder

(source files)

IFolder

(compiled files)

IFolder

IFile

(IProjectDescription)

IFile

How do you access

these items in Java?

10

Resources in Eclipse: Class hierarchy

How to navigate? [brief excerpt from the JavaDoc]

• IResource.exists(): boolean Check whether the resource exists

• IResource.getFullPath(): IPath Returns the full, absolute path of this

resource relative to the workspace.

• IResource.getLocationURI(): URI Get the URI of this ressource

• IContainer.members(): IResource[] Get handles to all resources contained here

• IContainer.getFile(String file): IFile Get a handle to a file contained here

• IFolder.create(…): void Create this folder (assuming it does not exist)

• IFile.create(…): void Create this file (assuming it does not exist)

Open that dialog with ”Ctrl + t”

11

Resources in Eclipse: Handles

• Access to a resource is managed by a ”handle”:

• ”There is no guarantee or requirement that the resource itself exists

until you try to do something with the handle.“ [Eclipse help]

petrinetModel: IFile

fullPath = ”/dk.dtu.imm.se2.petrinet/model/Petrinet.ecore”

IFile petrinetModel = modelFolder.getFile("Petinet.ecore");

MessageDialog.openInformation(shell, "petrinet model path",

petrinetModel.getFullPath().toString() + "\n" +

"File exists: " + petrinetModel.exists());

What will be

shown here?

12

Resources in Eclipse: URIs

Syntax for Uniform Resource Identifiers

<URI scheme>:<path>#<fragment>

Examples: – http://imm.dtu.dk/~pk/

– http://modeldiff.imm.dtu.dk/modeldiff/#documentation

– platform:/resource/dk.dtu.imm.se2.petrinet/plugin.xml

– platform:/plugin/org.eclipse.emf.ecore/model/Ecore.ecore#//EReference

URIs also in your models (as XMI):

– wiper.componentdefinition

– wipersystem.deployment

– test.petrinet

Resource is

located in the

workspace

Resource is

located in a

running plugin

Reference to an

EClass within the

EMF meta model

Platform independent!

13

"platform:/resource/CASETool-Examples/WiperSystem/controller.componentdefinition"

Resources in Eclipse: Load a Resource

A resource can be loaded with a given URI

• via the bundle of the local plugin activator:

platform:/resource/dk.dtu.imm.se2.dashboard/icons/dashboard.gif

• EMF provides simple methods for loading models:

1. Create resource set

2. ask it for a resource using a URI

final URL imageURL = PluginActivator.getDefault().getBundle().getEntry("icons/dashboard.gif");

final Image image = ImageDescriptor.createFromURL(imageURL).createImage();

final ResourceSet resourceSet = new ResourceSetImpl();

final URI uri = URI.createURI(

);

final Resource resource = resourceSet.getResource(uri, true);

final EObject compDef = resource.getContents().get(0);

Located in

workspace

Project Folder File

14

Resources in Eclipse: References

• Eclipse help (Help Help Contents):

Platform Plug-in Developer Guide Programmer’s Guide

Resources overview Resources and the file system

• Uniform Resource Identifier (URI) – Generic Syntax:

http://labs.apache.org/webarch/uri/rfc/rfc3986.html

15

Progress…

Topic Concepts Examples Slides

Resources in Eclipse No direct access!

Use “wrapper” for

accessing resources

IFile, IFolder, URI 9 – 14

Dialogs

OCL in EMF / GMF

GMF:

Graphical properties

in the model

GMF: Architecture

GMF: Decorator

16

Dialog: Examples

if (MessageDialog.openQuestion(shell,

“Disconnect?”,

“Do you really want to disconnect from the running simulation?")) {

…

new InputDialog(shell, "Name?", "Please enter a name.", "system1", null).open();

new ResourceDialog(shell,

"Select deployment", SWT.OPEN | SWT.SINGLE).open();

17

Dialog: More Examples

WorkspaceResourceDialog.openFileSelection(shell,

"Select files", "Please select input file(s)",

false, null, filters);

WorkspaceResourceDialog.openNewFile(shell, "Save file",

"Please select output file", null, null);

Suggested path

Filters for the files

List<ViewerFilter> filters = new ArrayList<ViewerFilter>();

filters.add(new ViewerFilter() {

@Override

public boolean select(Viewer viewer,

Object parentElement, Object element) {

if (element instanceof IFile) {

return ((IFile)element).

getFileExtension().equals("deployment");

} else return true;

}

});

18

Dialogs: Yet More Examples

MessageDialog dialog = new MessageDialog(shell,

"File already exists", image,

"'" + file.getName() + "' already exists.\nWhat do you want to do?",

MessageDialog.WARNING, buttons, 1);

String[] buttons = new String[]{

"Overwrite",

"Save as '" + fileAlternative.getName() + "'",

"Cancel“

};

MessageDialog dialog = new MessageDialog(shell,

"File already exists", image,

"'" + file.getName() + "' already exists.\nWhat do you want to do?",

MessageDialog.WARNING, buttons, 1);

switch (dialog.open()) {

case 0: return file;

case 1: return fileAlternative;

default: return null;

}

19

Dialogs: Which one?!

• Does a dialog already exist for my purpose?

– Yes? Use it!

– No? Pick the closet one, inherit from it, and adjust it for your needs!

• How do I find existing dialogs?

– Type Hierarchy of existing dialogs

– Plug-in Spy on open dialogs

Open with

Alt + Shift + F1

Quick Type Hierarchy

with Ctrl + t

20

Dialogs: References

• Eclipse Help (Help Help Contents):

Platform Plug-in Developer Guide > Programmer's Guide > Dialogs and wizards

• JavaDoc

• JFace Snippets: http://wiki.eclipse.org/JFaceSnippets

21

Progress…

Topic Concepts Examples Slides

Resources in Eclipse No direct access!

Use “wrapper” for

accessing resources

IFile, IFolder, URI 9 – 14

Dialogs Use existing ones!

(static & dynamic)

MessageDialog,

InputDialog,

ResourceDialog, …

16 – 20

OCL in EMF / GMF

GMF:

Graphical properties

in the model

GMF: Architecture

GMF: Decorator

22

OCL: in EMF and GMF

• What is wrong with the deployment?

– free_software is not on a node

– wiper_on_a_chip is on a node

• Goal: validate that the models are correct!

– Hard-coding constraints… but I am lazy…

– Model constraints in OCL (Object Constraint Language)

self.definition->size() > 0 and

self.definition.hardware self.definition->size() > 0 and

not self.definition.hardware

What is

wrong here?

23

OCL: Constraints for modeling

Constraint for

connections:

The messages at

the out-port must

be receivable at

the in-port!

24

OCL: Constraints for modeling

Constraint for

connections:

The messages at

the out-port must

be receivable at

the in-port! Context (self)

In OCL: self.source.definition.out->forAll( m1 | self.target.definition._in->exists(m2 | m1=m2 )) and

self.target.definition.out->forAll( m1 | self.source.definition._in->exists(m2 | m1=m2 ))

In OCL: self.

In OCL: self.source.definition.out->forAll( m1 | self.target.definition._in->exists(m2 | m1=m2 ))

In OCL: self.source.definition.out->forAll( m1 | self.target.definition._in->exists( ))

In OCL: self.source.

In OCL: self.source.definition.

In OCL: self.source.definition.out

In OCL: self.source.definition.out->forAll( self.target.definition._in )

25

OCL: brief overview

OCL expressions:

• start from the context object (in OCL called self)

• may access attributes and methods (by dot-notation and resp. names)

• may navigate along associations

• may call operations and built-in functions

OCL…

• … is independent from a concrete programing language and

is tuned to formulate typical constraints on MOF and UML models

• … also allows us to formulate pre and post conditions of methods

• … can be used to ”implement” some methods and derived attributes

• … can be used for validation of models

26

OCL: use in GMF

• Different kinds of OCL Constraints are supported by GMF editors:

– Live mode:

During work on model

(slide 23)

– Non-live mode:

Explicit validation

(slide 22)

– Severity:

• Information

• Warning

• Error

Context (self)

[ Examples in DeploymentEditor.gmfmap ]

27

OCL: Interactive Console

The Interactive OCL Console

allows to evaluate

OCL expressions live

Context (self)

must be selected

Evaluation

results

Code completion !!!

Select OCL

Console here

28

OCL: References

• OCL Definition: http://www.omg.org/spec/OCL/2.0/

• OCL in Eclipse: http://wiki.eclipse.org/MDT-OCL

• GMF Constraints in general: http://wiki.eclipse.org/GMF_Constraints

• Validation in GMF: http://wiki.eclipse.org/GMF_Tutorial_Part_2

• OCL in EMF (advanced!): http://www.eclipse.org/articles/article.php?file=Article-

EMF-Codegen-with-OCL/index.html

• OCL for GMF requires an additional feature installed (unfortunately):

Helpful plugins MDT OCL All-in-One

Tool for checking the correct syntact of OCL constraints and for evaluating

constraints at runtime (”Interactive OCL Console”):

From Update site:

http://download.eclipse.org/modeling/mdt/ocl/updates/releases

Install

”OCL All-in-One SDK” (latest version)

29

OCL Console ”M1 level” (design time)

30

Console ”M2 level” (runtime)

31

32

Progress…

Topic Concepts Examples Slides

Resources in Eclipse No direct access!

Use “wrapper” for

accessing resources

IFile, IFolder, URI 9 – 14

Dialogs Use existing ones!

(static & dynamic)

MessageDialog,

InputDialog,

ResourceDialog, …

16 – 20

OCL in EMF / GMF Constraints in the model:

Object Constraint

Language

Deployment model;

OCL Console

22 – 31

GMF: Graphical

properties in the

model

GMF: Architecture

GMF: Decorator

33

Model vs. View: Reminder

[ From Lecture 1: SE2-L01.pdf ]

34

Model vs. View

Model: instance of a meta model

A view on the

Dashboard

meta model

Several views

on a Dashboard

model

What is a model?

What is a view?

A view on a model is one representation of

the entire model or of a part of the model.

There might be several representations of the

same model element in a view.

In the model, each element exists only once!

35

Model vs. View: GMF

Contents of the ”_diagram” file:

• Each graphical element is stored as

a ”Node”

• GMF stores graphical information

for each Node:

position, size, font style, colours, …

contains

the model

is just one

representation

36

Model vs. View: Dashboard Motivation

Dashboard

model(s)

Dashboard editor Dashboard view

Creating

Dashboard

model

Visualizing

Dashboard model

during simulation

What is the

problem?

All graphical

information is

missing in the

model!

.dashboar

d

_diagram

37

Model vs. View: Storing graphical details in the model

1. Make your model capable of storing the graphical details

2. Install a listener on graphical

elements which updates the

location attributes each time

a figure is created/moved

3. Hook listener into your editor, e.g. in ResourceSetInfo in DiagramDocumentProvider

protected class ResourceSetInfo extends ElementInfo {

/** @generated NOT */

private GraphicElementListener graphicElementListener = new GraphicElementListener();

/** @generated NOT */

public ResourceSetInfo(IDiagramDocument document, IEditorInput editorInput) {

[...]

getResourceSet().getResources().get(0).eAdapters().add(graphicElementListener);

}

/** @generated NOT */

public void dispose() {

getResourceSet().getResources().get(0).eAdapters().remove(graphicElementListener);

[...]

}

38

Model vs. View: Graphical Element Listener

public class GraphicElementListener extends EContentAdapter {

private NotificationFilter modifiedFilter;

public GraphicElementListener() {

modifiedFilter = NotificationFilter.createEventTypeFilter(Notification.SET).or(

NotificationFilter.createEventTypeFilter(Notification.UNSET)).or(

NotificationFilter.createEventTypeFilter(Notification.ADD)).or(

NotificationFilter.createEventTypeFilter(Notification.REMOVE));

}

public void notifyChanged(Notification notification) {

if (notification.getNotifier() instanceof EObject) {

super.notifyChanged(notification);

}

if (modifiedFilter.matches(notification)

&& (notification instanceof ENotificationImpl)

&& (notification.getNotifier() instanceof EObject)) {

ENotificationImpl eNotification = (ENotificationImpl) notification;

EObject eNotifier = (EObject) eNotification.getNotifier();

if (NotationPackage.eINSTANCE.getBounds().isSuperTypeOf(eNotifier.eClass())) {

updateNodeBounds(eNotification, eNotifier);

}

}

}

private void updateNodeBounds(ENotificationImpl eNotification, EObject eNotifier) {

int featureID = eNotification.getFeatureID(EAttribute.class);

EObject modelElement = ((View) eNotifier.eContainer()).getElement();

if (modelElement instanceof ILocation){

ILocation location = (ILocation) modelElement;

switch (featureID) {

case NotationPackage.BOUNDS__X:

location.setX(eNotification.getNewIntValue());

break;

case NotationPackage.BOUNDS__Y:

location.setY(eNotification.getNewIntValue());

break;

}

}

}

}

filter for notification types

handle the notification event call updateNodeBounds

Update the location for all ILocation objects:

call setX(…) and setY(…)

extends Adapter (Listener)

39

Progress…

Topic Concepts Examples Slides

Resources in Eclipse No direct access!

Use “wrapper” for

accessing resources

IFile, IFolder, URI 9 – 14

Dialogs Use existing ones!

(static & dynamic)

MessageDialog,

InputDialog,

ResourceDialog, …

16 – 20

OCL in EMF / GMF Constraints in the model:

Object Constraint

Language

Deployment model;

OCL Console

22 – 31

GMF:

Graphical properties

in the model

Model vs. View Saving the position of

figures in the model

33 – 38

GMF: Architecture

GMF: Decorator

40

GMF Architecture

[Introduction to GMF, EclipseCon 2006]

The important relevant parts:

• .diagram.edit.commands Commands for creating elements

• .diagram.edit.parts Controller (and views!) for all model elements

• .diagram.edit.policies General editing rules and restrictions

• .diagram.part Main classes

(Editor, Wizard, Palette, Toolbar, Model provider, …)

• .diagram.providers Item providers for edit-parts

41

fig

View

(Figures)

42

GMF Architecture: MVC pattern

Controller

(EditParts)

Model

Located in you

EMF model plugin

Located in

.diagram.edit.parts

Also located in

.diagram.edit.parts

Observer

pattern

(Listeners)

Direct

access

Model

Root

“Diagram”

EditPart

Diagram

Figure

42

MVC excursion: GMF vs. Pattern idea

fig

View Controller Model

[ From Lecture 2: SE2-L02.pdf ]

• Controller and View are

tightly coupled in GMF!

• No queries from the view

to the model

43

GMF Architecture: The EditParts

• EditParts are controllers

– Create Figures

– Define Figure Layout

– Set graphical properties (not stored in the model)

– Contain Figures

• Let’s have a look at the PlaceEditPart of the Petrinet editor…

• Tipp:

Create your own package for your customized figures and integrate your figures in the .gmfgraph file

(unless you need to customize what is not possible to define in gmfgraph)

!!!

Dashboard editor does

probably not need

customized figures!

44

Progress…

Topic Concepts Examples Slides

Resources in Eclipse No direct access!

Use “wrapper” for

accessing resources

IFile, IFolder, URI 9 – 14

Dialogs Use existing ones!

(static & dynamic)

MessageDialog,

InputDialog,

ResourceDialog, …

16 – 20

OCL in EMF / GMF Constraints in the model:

Object Constraint

Language

Deployment model;

OCL Console

22 – 31

GMF:

Graphical properties

in the model

Model vs. View Saving the position of

figures in the model

33 – 38

GMF: Architecture Model-View-Controller

pattern

EditParts, Figures,

ModelElements

40 – 43

GMF: Decorator

45

Decorator: Examples

• A decorator ’decorates’ an existing element by adding something

– Overlay images, examples above

– Adding behavior to a method by delegation, e.g. streams

– Adding components on a GUI, e.g. scrollbars

• Advantages:

– Existing element is not changed!

– Different decorators possible, either nested or alternative

Where are the

decodators?

46

Decorator: The Pattern

Nested decorators:

1. the image

2. inner frame

3. outer frame

[ Design Patterns – Simply ]

47

Decorators: Realization in GMF

1. Implement a decorator by extending AbstractDecorator

• overwrite the refresh() method

• make sure changes to model elements are recognized:

install an observer on the model element and handle updates

2. Implement a decorator provider by extending AbstractProvider

and implementing IDecoratorProvider

• responsible for the creation of the decorator for the correct model elements

3. Register the decorator provider at the extension point: org.eclipse.gmf.runtime.diagram.ui.decorator.providers

[details in http://eclipsezilla.eclipsecon.org/php/attachment.php?bugid=3624]

48

Decorator: References

• Gamma, E.; Helm, R.; Johnson, R. & Vlissides, J.

Design Patterns: Elements of Reusable Object-Oriented Software

Addison-Wesley, 1995

• Design Patterns – Simply:

http://sourcemaking.com/design_patterns/decorator

• Decorating shapes in GMF (slides 44-51):

http://eclipsezilla.eclipsecon.org/php/attachment.php?bugid=3624

• GMF Tutorial:

http://wiki.eclipse.org/GMF_Tutorial_Part_2#Shortcuts

49

Summary

Topic Concepts Examples Slides

Resources in Eclipse No direct access!

Use “wrapper” for

accessing resources

IFile, IFolder, URI 9 – 14

Dialogs Use existing ones!

(static & dynamic)

MessageDialog,

InputDialog,

ResourceDialog, …

16 – 20

OCL in EMF / GMF Constraints in the model:

Object Constraint

Language

Deployment model;

OCL Console

22 – 31

GMF:

Graphical properties

in the model

Model vs. View Saving the position of

figures in the model

33 – 38

GMF: Architecture Model-View-Controller

pattern

EditParts, Figures,

ModelElements

40 – 43

GMF: Decorator Decorator design pattern Decorating figures;

Initial state in

component definition

45 – 48

50

Questions?

1. Questions about this tutorial?

2. Questions about the tutorials in general?

3. Questions about the project?

Think about where to

use these technologies

in your project!