Eclipse und EMF'Edit Tutorial

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Eclipse und EMF.Edit Tutorial
Steffen Becker (sbecker_at_ipd.uka.de)
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Eclipse

• Eclipse SDK is in fact two parts
• Eclipse RCP
• Eclipse JDT
• When programming Eclipse plugins most of the work
  deals with RCP and related plugins
• Examples from the PCMBench
• Tabbed Property Sheets
• EMF
• GEF
• Actions
• Resource Plugin
• Workbench

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Eclipse Plugin Concept

• Eclipse RCP defines the concepts of Extensions
  and Extension Points
• Extension Points are point where functionality
  can be added by other plugins
• Extensions contribute functionality to extension
  points
• Plug and Socket Icons

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Reading Code

• When reading plugin code, take a look at
  extensions
• Extensions often declare a implementing class for
  the added functionality
• Look in the extension point docu to find out
  about the semantics

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Examples

• Go to Eclipse and look at examples in the
  PCMBench
• Hands-on demo
• Ask, if anything seems unclear

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Eclipse EMF

• EMF can be regarded as EMOF implementation
• Code generation facilities from ECORE to
• Model code
• Editor support code (platform independent)
• Sample Eclipse Editor (platform dependent)
• Unit test stubs
• Optionally OCL constraint checks, requires
  modified generator

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EMF Model code
public interface Book extends EObject String
getTitle() void setTitle(String value) int
getPages() void setPages(int value)
public class BookImpl extends EObjectImpl
implements Book ... protected static final
int PAGES_EDEFAULT 0 protected int pages
PAGES_EDEFAULT public int getPages() return
pages public void setPages(int newPages)
int oldPages pages pages newPages if
(eNotificationRequired()) eNotify(new
ENotificationImpl(this, Notification.SET,
..., oldPages, pages)) ...
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References
public void setAuthor(Writer newAuthor) Writer
oldAuthor author author newAuthor
if(eNotificationRequired()) eNotify(new
ENotificationImpl(this, ...))
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References
public Writer getAuthor() if (author ! null
author.eIsProxy()) Writer oldAuthor
author author(Writer)eResolveProxy((InternalE
Object)author) if (author ! oldAuthor)
if (eNotificationRequired()) eNotify(new
ENotificationImpl(this, Notification.RESOLVE
, ...)) return author
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So much to it

• There is more about EMF Generator
• Examples
• Factories
• Switch Classes
• Adapter Factories
• Refer to the EMF bible or online tutorials or
  links in SDQ wiki
• Lets have a look at code again
• Questions?

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EMF Edit

• EMF Edit supports writing editors for EMF Models
• What is needed for this?
• GUI Support
• Observer Pattern
• Labels
• Model part of the MVC pattern (for list boxes,
  tables, etc)
• Property Sheet support
• Commands
• For Undo/Redo-Editing
• Well look at all of them now

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Observer

• We have seen this in the model code already
• Interface Notifier
• List of observer is called adapter
• Reasons for this name given soon

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Observer

• listeningAdapter new EContentAdapter()_at_Overri
  de
• public void notifyChanged(Notification
  notification)
• super.notifyChanged(notification)
• if (notification.getFeature().equals(attribute)
  notification.getEventType()
  Notification.SET)
• doSth()
• emfObject.eAdapters().add(listeningAdapter)

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Label

• Label need mainly two methods getText and
  getLabel
• Interface IItemLabelProvider
• Instead of adding IItemLabelProvider to the model
  class directly, a different class is used

ItemProviderAdapter
EMFModelObject
EMFModelObject
EMFModelObjectItemProvider
EMFModelObject
IItemLabelProvider
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ItemProviderFactory

• Where do the item providers come from?
• A factory is generated for thisEMFModelPackage
  ItemProviderAdapterFactory
• The factory always provides ItemProviderAdapter
• Pass in a known EMFModelObject of Package
  EMFModelPackage

xxItemProviderAdapterFactory
ltltcreategtgt
EMFModelObject
EMFModelObject
EMFModelObjectItemProvider
EMFModelObject
IItemLabelProvider
ItemProviderAdapter
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Eclipse Labels

• IItemLabelProvider is Eclipse independent
• ILabelProvider is needed for the Eclipse GUI
  elements
• Result Another adapter is needed
• AdapterFactoryLabelProvider converts
  IItemLabelProvider into ILabelProvider

ILabelProvider
AdapterFactoryLabelProvider
xxItemProviderAdapterFactory
EMFModelObject
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Delegation
IContentProvider
IContentProvider
DelegatingAdapterFactoryContentProvider
AdapterFactoryContentProvider

• Delegation is the standard method to change
  behaviour while keeping the interface
• Especially, if some participants are generated
• You only need the capability to change the
  factory. Sometimes this can be done via
  inheritance and overriding

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Content (for Listboxes, TreeControls, )

• Content needs methods to get the structure
  getParent, getChildren,
• Interface IItemContentProvider
• Again, instead of adding IItemContent Provider to
  the model class directly, a different class is
  used
• The idea is to use the same adapter as before

ItemProviderAdapter
EMFModelObject
EMFModelObject
EMFModelObjectItemProvider
EMFModelObject
IItemContentProvider
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ItemProviderFactory Deja vu

• Where do the item providers come from?
• A factory is generated for thisEMFModelPackage
  ItemProviderAdapterFactory
• The factory always provides ItemProviderAdapter
• Pass in a known EMFModelObject of Package
  EMFModelPackage

xxItemProviderAdapterFactory
ltltcreategtgt
EMFModelObject
EMFModelObject
EMFModelObjectItemProvider
EMFModelObject
IItemxxxProvider
ItemProviderAdapter
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Eclipse Content

• IItemContentProvider is Eclipse independent
• IContentProvider (or special subclasses) are
  needed for the Eclipse GUI elements
• Result Another adapter is needed
• AdapterFactoryContentProvider converts
  IItemContentProvider into IContentProvider

IContentProvider
AdapterFactoryContentProvider
xxItemProviderAdapterFactory
EMFModelObject
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Now it becomes boring

• The same is true also for
• IEditingDomainItemProvider
• IStructuredItemContentProvider
• ITreeItemContentProvider
• IItemLabelProvider
• IItemPropertySource

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PropertySources

• public interface IItemPropertySource
• /
• This does the same thing as
• IPropertySource.getPropertyDescriptors.
• /
• List getPropertyDescriptors(Object object)
• /
• This returns the property descriptor with
  the given ID.
• /
• IItemPropertyDescriptor getPropertyDescriptor(
  Object object, Object
  propertyID)
• /
• This returns the value to be edited.
• /
• Object getEditableValue(Object object)

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EditingDomain/Commands
ResourceSet
Resource
Resource
Command
Command-Stack
Model-Instance

• EditingDomains contain a CommandStack and a
  ResourceSet
• Commands can be executed via the command stack
  with undo/redo support
• Commands can be created using the EditingDomain
  as factory or directly

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TransactionalEditingDomain
ResourceSet
Resource
Resource
Command
RO wo/ Transaction
Command-Stack
Model-Instance

• TransactionalEditingDomain ensure consistent
  multiple access
• Writing wo/ transaction results in an exception
• For reading a transaction is optional
• There is a registry of all TransactionalED
• Important RecordingCommand

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RecordingCommand

• RecordingCommand recCommand new
  RecordingCommand(editingDomain)
• _at_Override
• protected void doExecute()
• element.eSet(attribute, valueText.getText())
  

Also note the use of InnerClasses! This is very
common in Eclipse GUI and Command Programming
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Hands-on

• We now take a tour through the code again
• Also lets define code to review
• TabPropertySheets
• CommonNavigatorView
• Some RCP integration classes
• Wizard
• ProjectNature