Xtext. Introduction and Real World Samples. Hendrik Bünder, itemis AG. itemis AG

Transcription

1 Xtext Introduction and Real World Samples Hendrik Bünder, itemis AG

2 Who is this guy? Hendrik Bünder IT-Consultant

3 Agenda Introduction to Xtext What, How, Why? Common DSLs DSLs that no longer impress anybody. Advanced Use Cases for DSLs The fancy real world stuff Discussion What you always wanted to know about DSLs and Xtext

4 Connecting to what I know you (should) know. Xtext is a language workbench External DSL Xtext grammar notation is central artifact for DSL definition (EBNF++) Xtext DSL by default have a textual representation The concrete syntax is parsed using an ANTLR parser Generator templates implemented using Xtend

5 Language Workbenches Xtext Since 2006 developed by itemis Eclipse-base Part of the Eclipse Modeling Project Eclipse Project since 2008 Open-Source (EPL) Textuall DSLs Parser-based Grammar as central artifact ANTLR Parser

6 Structure and Runtime

7 Structure and Runtime

8 Structure and Runtime

9 Structure and Runtime

10 Structure and Runtime

11 Structure and Runtime

12 Structure and Runtime

13 Structure and Runtime

14 Structure and Runtime

15 Structure and Runtime

16 Structure and Runtime

17 ScreenFlow Entities Widgets Gui Forms Services Datatypes Constraints Exceptions LANGUAGES Mapping

18 Common DSLs En ti ty D `S e SL En e m u S D io n t ra rv i ce DS L L P er s i SL D e c s te n

19 Model-Based Migration UML-2-Xtext

20 Migratin a legacy system Insurance Life System 15 million LOC 60% RPG 40% Java Hardware IBM iseries Hardware (AS/400) User interface IBM Webfacing Database DB/2

21 Migration Why? What? How? Why? Ending support A desire to reduce maintenance and working costs Retiring know-how A desire to increase attractiveness and market acceptance What? Data, user interfaces, ports, functions How? Redevelopment, fully automated, semi-automated (= model-based)

22 Model-Based Migration Legacy system (e.g. Forms / RPG) Model-based migration with adapted tools Target system 22

23 The Approach 23

24 UI Replatforming: Motivation Web solution exists (IBM WebFacing), but still has a text-mode look&feel Hard to internationalize and make accessible Still bound to mainframe platform and RPG Not future-proof 24

25 UI-Replatforming: Target Architecture J2EE Spring Framework JavaServer Faces (JSF) 2.x Facelets Apache Tobago ( grid layout) Data binding using Java Expression Language CSS, JavaScript 25

26 UI-Replatforming: DSLs und Generatoren BO DSL models BO generat or BO Java Beans use Viewmodel DSL models use Viewmodel generator use/extend Viewmodel Java Beans Screen DSL models Screen generator use JSF Facelets 26

27 Screen DSL <-> Screen Preview 27

28 The result 1 million loc XHTML 4.3 milllion loc Java loc model 3 million loc Java 7 million loc RPG 28

29 Testing Problem No automated Tests Solution Record test cases in legacy system in browser (IBM WebFacing) Recording done with HP Quality Center Transform recorded legacy tests to Test DSL Generate Selenium tests out of test cases in Test DSL Test migrated system Prerequisite Ensure that UI widget ID is preserved 29

30 Testing Terminal 30

31 Testing IBM WebFacing 31

32 Testing - HP Quality Center (UFT) - UFT DSL 32

33 Testing - Test DSL 33

34 Testing Generated Selenium Test 34

35 Behavior-Driven UI Testing

36 Screen Feature Mapping Flexible Generators Automatically Executable Test Cases

37 We also got DSLs for.. Traceability Router Configuration UI Descriptions Docker Requirements Business Rules Statemachines Typesystems Embedded Development

38 Industry-proven

39 Take away Xtext is a powerful language workbench to create state of the art languages and editors Industry-proven for Domain-specific languages Model-based migration Testing Typesystems. Xtext is backed by a vivid open-source comunity Feel free to join the Xtext community

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41 Thank you for your attention! itemis AG Am Brambusch D Lünen