The document discusses domain-specific languages (DSLs) and how the Xtext framework can be used to define and implement DSLs. It provides an example grammar for a simple DSL for modeling datatypes and entities. Xtext allows defining the grammar which is then used to generate a metamodel, parser, and other artifacts needed for the DSL.

1. Textual Modeling Framework
Jan Koehnlein - Sven Efftinge
itemis
Wednesday, March 25, 2009

2. Domain-Specific Language (DSL)
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3. Domain-Specific Language (DSL)
A DSL is a formal, processable language
targeting at a specific viewpoint or
aspect of a software system.
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4. Domain-Specific Language (DSL)
A DSL is a formal, processable language
targeting at a specific viewpoint or
aspect of a software system.
It’s semantics, flexibility and notation is
designed in order to support working
with that viewpoint as good as possible.
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5. Why DSLs?
• higher abstractions
• avoid redundancy
• separation of concerns
• use domain concepts
(Ubiquitous Language)
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6. The challenge
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7. Complicated
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8. Complicated & Expensive ?
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9. licensed by http://www.wordle.net/
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10. How we address this with
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11. Convenience
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21. grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Model:
(types+=Type)*;
Type:
Datatype | Entity;
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

22. Grammar Definition
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Model:
(types+=Type)*;
Type:
Datatype | Entity;
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

23. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Model:
(types+=Type)*;
Type:
Datatype | Entity;
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

24. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Model:
(types+=Type)*;
Type:
Datatype | Entity;
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

25. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Model:
Parser (types+=Type)*;
Rules Type:
Datatype | Entity;
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

26. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Containment
Reference
Model:
Parser (types+=Type)*;
Rules Type:
Datatype | Entity;
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

27. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Containment
Reference
Model:
Parser (types+=Type)*;
Cardinality
Rules Type:
Datatype | Entity;
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

28. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Containment
Reference
Model:
Parser (types+=Type)*;
Cardinality
Rules Type:
Datatype | Entity;
Alternatives
Datatype:
'datatype' name=ID;
Entity:
'entity' name=ID '{'
(features+=Feature)*
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

29. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Containment
Reference
Model:
Parser (types+=Type)*;
Cardinality
Rules Type:
Datatype | Entity;
Alternatives
Datatype:
'datatype' name=ID;
Call to
Entity:
Terminal
'entity' name=ID '{'
(features+=Feature)*
Rule
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

30. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Containment
Reference
Model:
Parser (types+=Type)*;
Cardinality
Rules Type:
Datatype | Entity;
Alternatives
Datatype:
'datatype' name=ID;
Call to
Entity:
Keywords Terminal
'entity' name=ID '{'
(features+=Feature)*
Rule
'}';
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

31. Grammar Definition Terminal Rule Import
grammar org.xtext.example.MyDsl
Derived with org.eclipse.xtext.common.Terminals
Metamodel generate myDsl quot;http://www.xtext.org/example/MyDslquot;
Containment
Reference
Model:
Parser (types+=Type)*;
Cardinality
Rules Type:
Datatype | Entity;
Alternatives
Datatype:
'datatype' name=ID;
Call to
Entity:
Keywords Terminal
'entity' name=ID '{'
(features+=Feature)*
Cross Rule
'}';
Reference
Feature:
type=[Type] name=ID;
Wednesday, March 25, 2009

32. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

33. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

34. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

35. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

36. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

37. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

38. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

39. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

40. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

41. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

42. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

43. Metamodel Derivation
MyDsl
grammar org.xtext.example.MyDsl
with org.eclipse.xtext.common.Terminals
Model
generate myDsl
quot;http://www.xtext.org/example/MyDslquot;
Model: *
Type
(types+=Type)*;
name: String
Type:
Datatype | Entity;
Datatype: Datatype Entity
'datatype' name=ID;
Entity:
'entity' name=ID '{' type
(features+=Feature)* *
'}'; Feature
*
name: String
Feature:
type=[Datatype] name=ID;
Wednesday, March 25, 2009

44. licensed by http://www.wordle.net/
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45. Based on
the grammar and Ecore models,
Xtext provides you with sensible
default implementations.
licensed by http://www.wordle.net/
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46. Validation
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47. Wednesday, March 25, 2009

48. Wednesday, March 25, 2009

49. Wednesday, March 25, 2009

50. Wednesday, March 25, 2009

51. Customizing the LabelProvider
public class MySpecialLabelProvider
extends DefaultLabelProvider {
public String label(Feature f) {
return f.getName()+quot;:quot;+f.getType().getName();
}
}
‣Naming Convention
‣Polymorphic Dispatch
‣Fault tolerance
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52. Flexibility
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53. licensed by http://www.wordle.net/
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54. Dependency management
licensed by http://www.wordle.net/
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55. Dependency management
licensed by http://www.wordle.net/
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56. Dependency management
licensed by http://www.wordle.net/
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57. Dependency management
licensed by http://www.wordle.net/
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58. Dependency management
licensed by http://www.wordle.net/
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59. MyCustomLabelProvider
licensed by http://www.wordle.net/
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60. Dependency Injection
with Google fGuice
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61. Dependency Injection
with Google fGuice
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62. Dependency Injection
with Google fGuice
‣No dependency to concrete implementation
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63. Dependency Injection
with Google fGuice
‣No dependency to concrete implementation
‣No explicit construction
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64. Dependency Injection
with Google fGuice
‣No dependency to concrete implementation
‣No explicit construction
‣Easy testing
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65. Dependency Injection
with Google fGuice
‣No dependency to concrete implementation
‣No explicit construction
‣Easy testing
‣Easy composition
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66. Configuration of
Components in Xtext
AbstractDeclarativeModule
DefaultRuntimeModule DefaultUIModule
From Xtext
Your Project
GeneratedRuntimeModule GeneratedUIModule
RuntimeModule UIModule
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67. Configuration of
Components in Xtext
/**
* used to register components to be used within the IDE.
*/
public class DomainmodelUiModule
extends GeneratedDomainmodelUiModule {
@Override
public Class<? extends ILabelProvider> bindILabelProvider() {
return MySpecialLabelProvider.class;
}
}
Wednesday, March 25, 2009

68. and Equinox
Injector is created during Bundle.start(...)
@Override
public void start(BundleContext context) throws Exception {
super.start(context);
INSTANCE = this;
injector = Guice.createInjector(
new DomainmodelRuntimeModule(),
new DomainmodelUiModule());
}
Wednesday, March 25, 2009

69. and Equinox
ExecutableExtensions are created via
IExecutableExtensionFactory
<extension
point=quot;org.eclipse.emf.ecore.extension_parserquot;>
<parser class=quot;my.pack.DomainmodelExecutableExtensionFactory:
org.eclipse.xtext.resource.XtextResourceFactoryquot;
type=quot;dmodelquot;>
</parser>
</extension>
Wednesday, March 25, 2009

70. Composable
Code Generator
‣ generator is composed of “fragments”
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71. Composable
Code Generator
‣ generator is composed of “fragments”
‣ fragments can contribute to:
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72. Composable
Code Generator
‣ generator is composed of “fragments”
‣ fragments can contribute to:
‣ Manifest.MF
Wednesday, March 25, 2009

73. Composable
Code Generator
‣ generator is composed of “fragments”
‣ fragments can contribute to:
‣ Manifest.MF
‣ plugin.xml
Wednesday, March 25, 2009

74. Composable
Code Generator
‣ generator is composed of “fragments”
‣ fragments can contribute to:
‣ Manifest.MF
‣ plugin.xml
‣ Guice modules
Wednesday, March 25, 2009

75. Composable
Code Generator
‣ generator is composed of “fragments”
‣ fragments can contribute to:
‣ Manifest.MF
‣ plugin.xml
‣ Guice modules
‣ Add your own fragments
Wednesday, March 25, 2009

76. Future Plans
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77. Galileo
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78. Galileo
• Index
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79. Galileo
• Index
• Enum Rules
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80. Galileo
• Index
• Enum Rules
• Bug fixing / Performance Tuning
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81. Galileo
• Index
• Enum Rules
• Bug fixing / Performance Tuning
• Documentation
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82. Galileo
• Index
• Enum Rules
• Bug fixing / Performance Tuning
• Documentation
• Sugar (Wizards, Tutorials, etc.)
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83. Post Galileo
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84. Post Galileo
‣ More UI features
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85. Post Galileo
‣ More UI features
‣Basic Language Libraries
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86. Post Galileo
‣ More UI features
‣Basic Language Libraries
‣“Eat your own dog food”
continued
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87. Thank you very much for listening
Visit the project’s web site :
www.xtext.org
Copyright 2009 by itemis
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88. Convenient & Flexible
Wednesday, March 25, 2009