Difference between revisions of "Wire EMF Databinding RCP"

Revision as of 02:48, 11 July 2007

THIS IS AN ARTICLE WORK IN PROGRESS (Bug 195163)

Abstract/Requirements Definition

I'm trying to implement a fairly simple address book application on top of RCP using frameworks provided by Eclipse in 3.3. There's also focus on how to structure and design an RCP to be as extensible and as flexible as possible, including theming, internationalization, datastorage independency, ... .

Setup the Toolchain

1. Eclipse 3.3 for RCP-Developers (available from http://www.eclipse.org/downloads)
2. EMF using the Update-Manager (Help>Software Updates>Find and Install)
3. Derby-Plugins (available from http://db.apache.org/derby/derby_downloads.html)
   To install:
   1. Stop your eclipse (if running)
   2. Unzip „derby.zip“s (as of this writing derby_core_plugin_10.2.2.485682.zip and derby_ui_plugin_1.1.0.zip) into your %ECLIPSE_HOME/plugin directory
   3. Start up eclipse
4. iBatis (available from http://ibatis.apache.org)
5. Fetch application icons (e.g. available from http://websvn.kde.org/trunk/KDE/kdelibs/pics/oxygen/ using your favorite SVN-Client)
6. (Optional) Visual-Database Design
   1. Install Clay for Eclipse (available from http://www.azzurri.jp/en/software/clay/)
   2. Download Clay-Utils used for creation of DDL and documentation (available from http://publicsvn.bestsolution.at/repos/java/clayUtils/release/at.bestsolution.clayutils-nodeps-0.0.7.jar)
   3. DDL-Utils to create database DDL for any database you want (available from http://db.apache.org/ddlutils)
7. (Optional) Subclipse for Version-Control (available from http://subclipse.tigris.org)

Application Design

Plugin-Design

at.bestsolution.addressbook

The main RCP-Application

at.bestsolution.addressbook.ui

This plugin provides the UI bits (ViewPart, ...) for the addressbook application.

at.bestsolution.addressbook.ui.theme

This plugin addresses the themeability of the application by providing a plugable theme-API. It will by default provide a standard theme.

at.bestsolution.addressbook.core

This plugin provides the none GUI bits for the application like Command-Definitions, handlers, ...

at.bestsolution.addressbook.core.model

This plugin provides the model implementation created using EMF

at.bestsolution.addressbook.core.datasource

This plugin will provide the API to provide plugable datasources in our case

at.bestsolution.addressbook.core.datasource.xmi

This plugin provides a datasource implementation on top of XMI (directly supported by EMF)

at.bestsolution.addressbook.core.datasource.iBatis

This plugin provides a datasource implementation on top of iBatis

Plugin Overview

Domain Model

The domain model is fairly simple and can be represented by 2 classes as shown in the diagram below. The only interesting thing is that there's a bidirectional relationship between Person(Attribute: primaryAddress) and Address(Attribute: person).

Hands on practice or „Let's begin our journey“

Implementing at.bestsolution.addressbook.core.model

Create an EMF-Project

1. Open the "New Project Wizard"
2. Select Eclipse Modeling Framework
   
3. Name the project "at.bestsolution.addressbook.core.model"
   
4. The resulting workspace looks like this
   

Create the Ecore-Model

1. Select Example EMF Model Creation Wizards > Ecore Model
   
2. Name the model "addressbook.ecore"
   
3. Open the Properties-View (Window > Show View > Others ...)
   
4. Select the root node currently shown in the editor as null
   
5. Editing the properties in the property view
   

Now we have to add our Domain-Objects Person and Address to the Ecore-Model:

1. Right click on the addressbook-package you have created above and select
2. Set the following properties (in the Properties View)
   Name: Person
3. Right click the Person and select "New Child > EAttribute"
4. Set the following properties (in the Properties View)
   Name: surname
   EType: EString
5. Right click the Person and select "New Child > EAttribute"
6. Set the following properties (in the Properties View)
   Name: givenname
   EType: EString
7. Right click the Person and select "New Child > EAttribute"
8. Set the following properties (in the Properties View)
   Name: birthday
   EType: Edate
9. Right click on the addressbook-package you have created above and select "New Child > EClass"
10. Set the following properties (in the Properties View)
    Name: Address
11. Right click the Address and select "New Child > EAttribute"
12. Set the following properties (in the Properties View)
    Name: street
    EType: EString
13. Right click the Address and select "New Child > EAttribute"
14. Set the following properties (in the Properties View)
    Name: zip
    EType: EString
15. Right click the Address and select "New Child > EAttribute"
16. Set the following properties (in the Properties View)
    Name: city
    EType: EString
17. Right click the Address and select "New Child > EAttribute"
18. Set the following properties (in the Properties View)
    Name: country
    EType: EString

After having done this your model should look like the following:

Next thing we have to model is the bidirectional relation between Person and Address like we defined it in our UML-Class Diagramm. In EMF such a relation can be expressed as an EReference in conjunction with an EOpposite:

1. Right click the Person and select "New Child > EReference"
2. Set the following properties (in the Properties View)
   Name: primaryAddress
   EType: Address
   Containment: true
3. Right click the Address and select "New Child > EReference"
4. Set the following properties (in the Properties View)
   Name: person
   EType: Person
   EOpposite: primaryAddress
   Transient: true