Polyglot Multi-Paradigm. Modeling. MDA in the Real World. Stefan Tilkov

Transcription

1 Polyglot Multi-Paradigm Modeling MDA in the Real World Stefan Tilkov

2 What I ll Talk About How I define MDA What a typical tool chain looks like Real-world examples How UML/MOD, EMF, and DSLs relate What alternatives exist for modeling What all of this might mean for you

3 What is MDA? A development methodology A hype Lots of theory Much skepticism No silver bullet

4 Pragmatic MDA In essence, MDA is about creating one or more formal, machinereadable models, transforming them into other models and code with the goal of automating development.

5 MDA/MDD Bottom-up Developers hate doing boring stuff Redundancy is bad Repeatability is good Flexibility is awesome Good developers automate their work That s what MDA is about

6 You ve been doing it Chances are, you have been doing MDA/MDD for a while Model is just an abstraction - your model might have been a text file Laziness is an asset Key is repeatability

7 MDA & Code Generation Typically (?), code is generated directly from a UML model Model-to-model transformation is not (yet) mainstream Strict forward-engineering approach No wizard-like generate once No roundtrip engineering But always repeatable

8 A typical MDA tool-chain CASE Tool UML Model conforms to UML Profile match Code Generator Templates match Source Code Implemented System Manual Coding Compile/Build Cycle Frameworks Platform (J2EE,.NET, Mainframe,...)

9 Business Logic Infrastructure Knowledge MDA Tool Chain

10 MDA/MDD Value Reduced time & effort Increased quality Maintainability, Evolvability Testability

11 MDA/MDD Risks Acceptance Complexity Tool problems Process problems

12 UML and Alternatives A model-driven development (MDD) approach can be done based on MOF, EMF/ECORE UML DSLs, Software Factories, MS Oslo Many other technologies From a 10,000m view, this is irrelevant

13 DSLs and UML Profiles A DSL is a Domain Specific Language Two options for doing DSLs with MDA: Create custom meta-model with MOF Use UML Profiles instead Alternatives: Eclipse EMF ecosystem In many cases, UML hits the sweet spot Interesting options in Microsoft-land

14 Real-World Examples

15 Example 1 Telco Customer Care & Billing Plain MDA, Swing client, Innovator CASE, Carnot Workflow Model CIM/business architecture Map to IT architecture, annotate Generate EJB + tons of design pattern-driven code Include support for Web Services

16 UML Model XMI UML CASE Tool Code Generator Workflow Designer Source Code Manual Coding Compile/Build Cycle Implemented System Workflows Frameworks Workflow Engine J2EE SQL DDL RDBMS

17 Example 2: Large-scale Banking App Default MDA based on UML + Excel Generate EJB code from UML Create formula data and reports from Excel Diff against DB Implement ETL for Datawarehouse project by using UML & templating

18 UML Model Microsoft Excel XMI UML CASE Tool CSV Code Generator XML Source Code Manual Coding Compile/Build Cycle Implemented System Rules Frameworks Rule Engine J2EE SQL DDL RDBMS

19 Example 3: Strategic Meta-data Repository Create meta-model using UML (not MOF) Generate DDL + access code (Castor JDO) for RDBMS Model services using Eclipse-based UI

20 Meta-Model Eclipse UI UML CASE Tool RDBMS XMI SQL DDL Code Generator Code Generator Java COBOL

21 Example 4: ESB Interface Mapping Connect systems built with various technologies Map interfaces - technically and logic-wise Use of oaw Xtext to support textual mapping DSL

22 CASE Tool CASE Tool UML Model UML Model Templates DSL Manual Coding Mapping Model Manual Coding Generator Implemented System Implemented System ESB

23 Common Traits What do all these projects have in common? In no case, UML alone was used Nor any other single technology Additional ways to specify modeling information Integrated process

24 Microsoft & Modeling MS invests heavily in modeling MDA is equaled with UML and considered harmful (but no longer?) Microsoft s MOF-like DSL approach emphasizes specific over generic solutions Expect more and more DSL tools Not yet (widely) available Now superseded (?) by OSLO

25 Eclipse: EMF & Co. EMF + ECORE as core Eclipse technologies EMF, GMF, M2M, M2T,... Significant amount of tooling available and under development Still fairly new Gaining acceptance quickly

26 UML + Profiles in the Real World Sub-optimal in many regards Widely supported Widely understood Applicable for many scenarios

27 More Modeling Alternatives XML, XML Schema, WSDL Excel, Visio Java/C# + Annotations Dynamic Languages and Internal DSLs Text

28 External vs. Internal DSL cancel: transitions from submitted to cancelled, accept: transitions from received to accepted, from checking to checked event :cancel do transitions :from => :submitted, :to => :cancelled end event :accept do transitions :from => :received, :to => :accepted transitions :from => :checking, :to => :checked end

29 Rails ActiveRecord class Project < ActiveRecord::Base belongs_to :portfolio has_one :project_manager has_many :milestones has_and_belongs_to_many :categories end

30 Generated Methods class Project < ActiveRecord::Base belongs_to :portfolio has_one :project_manager Project.portfolio Project.portfolio=(portfolio) Project.portfolio.nil? Project.project_manager, Project.project_manager=(project_manager) Project.project_manager.nil? has_many :milestones Project.milestones.empty? Project.milestones.size Project.milestones Project.milestones<<(milestone) Project.milestones.delete(milestone) Project.milestones.find(milestone_id) Project.milestones.find(:all, options) Project.milestones.build, Project.milestones.create has_and_belongs_to_many :categories Project.categories.empty? Project.categories.size Project.categories Project.categories<<(category1) Project.categories.delete(category1) end

31 Harvesting Tremendous value is contained in existing systems Models do not exist or are incorrect Extract business logic information from existing applications

32 Conclusion Accepting MDA/MDD is not tied to any particular modeling approach Models and standards matter less than you think Mix and match paradigms as you see fit The key is getting control of your code system

33 Q&A innoq Deutschland GmbH innoq Schweiz GmbH Halskestraße 17 Gewerbestrasse 11 D Ratingen CH-6330 Cham Tel Tel Fax Fax innoq Weblog