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• Getting Started
• Installation
  • Install Pre-Configured Eclipse With Xtext
  • Install Xtext From Update Site
• 5 Minutes Tutorial
  • Creating A New Xtext Project
  • Generating The Language Infrastructure
  • Try The Editor
  • Conclusion
• 15 Minutes Tutorial
  • Create A New Xtext Project
  • Write Your Own Grammar
  • Generate Language Artifacts
  • Run the Generated IDE Plug-in
  • Second Iteration : Adding Packages and Imports
• 15 Minutes Tutorial - Extended
  • Writing a Code Generator With Xtend
  • Unit Testing the Language
  • Creating Custom Validation Rules
• Reference Documentation
• Overview
  • What is Xtext?
  • How Does It Work?
  • Xtext is Highly Configurable
  • Who Uses Xtext?
  • Who is Behind Xtext?
  • What is a Domain-Specific Language
• The Grammar Language
  • A First Example
  • The Syntax
  • Ecore Model Inference
  • Grammar Mixins
  • Common Terminals
• Configuration
  • The Language Generator
  • Dependency Injection in Xtext with Google Guice
• Runtime Concepts
  • Runtime Setup (ISetup)
  • Setup within Eclipse-Equinox (OSGi)
  • Logging
  • Validation
  • Linking
  • Scoping
  • Value Converter
  • Serialization
  • Formatting (Pretty Printing)
  • Fragment Provider (Referencing Xtext Models From Other EMF Artifacts)
  • Encoding in Xtext
• IDE Concepts
  • Label Provider
  • Content Assist
  • Quick Fixes
  • Template Proposals
  • Outline View
  • Hyperlinking
  • Syntax Coloring
• Xtext and Java
  • Plug-in Setup
  • Referring to Java Elements using JVM Types
  • Referring to Java Types Using Xbase
  • Inferring a JVM Model
  • Using Xbase Expressions
  • Xbase Language Reference
  • Lexical Syntax
  • Types
  • Expressions
  • Extension Methods
• MWE2
  • Examples
  • Language Reference
  • Syntax Reference
• Xtend
  • Getting Started
  • Classes and Functions
  • Expressions
• Integration with EMF and Other EMF Editors
  • Model, Ecore Model, and Ecore
  • EMF Code Generation
  • XtextResource Implementation
  • Integration with GMF Editors
• Appendix
• Migrating from Xtext 1.0.x to 2.0
  • Take the Shortcut
  • Migrating Step By Step
  • Now go for then new features
• Migrating from Xtext 0.7.x to 1.0
  • Migrating Step By Step

Runtime Concepts

Xtext itself and every language infrastructure developed with Xtext is configured and wired-up using dependency injection. Xtext may be used in different environments which introduce different constraints. Especially important is the difference between OSGi managed containers and plain vanilla Java programs. To honor these differences Xtext uses the concept of ISetup (src)-implementations in normal mode and uses Eclipse's extension mechanism when it should be configured in an OSGi environment.

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Runtime Setup (ISetup)

For each language there is an implementation of ISetup (src) generated. It implements a method called createInjectorAndDoEMFRegistration(), which can be called to do the initialization of the language infrastructure.

Caveat: The ISetup (src) class is intended to be used for runtime and for unit testing, only. if you use it in a Equinox scenario, you will very likely break the running application because entries to the global registries will be overwritten.

The setup method returns an Injector, which can further be used to obtain a parser, etc. It also registers the Resource.Factory and generated EPackages to the respective global registries provided by EMF. So basically after having run the setup and you can start using EMF API to load and store models of your language.

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Setup within Eclipse-Equinox (OSGi)

Within Eclipse we have a generated Activator, which creates a Guice Injector using the modules. In addition an IExecutableExtensionFactory is generated for each language, which is used to create IExecutableExtensions. This means that everything which is created via extension points is managed by Guice as well, i.e. you can declare dependencies and get them injected upon creation.

The only thing you have to do in order to use this factory is to prefix the class with the factory MyDslExecutableExtensionFactory name followed by a colon.

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Logging

Xtext uses Apache's log4j for logging. It is configured using files named log4j.properties, which are looked up in the root of the Java classpath. If you want to change or provide configuration at runtime (i.e. non-OSGi), all you have to do is putting such a log4j.properties in place and make sure that it is not overridden by other log4j.properties in previous classpath entries.

In OSGi you provide configuration by creating a fragment for org.apache.log4j. In this case you need to make sure that there is not any second fragment contributing a log4j.properties file.