Code Generation Activity

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This page describes code generation approaches, and tools, developed at the University of Southampton between 2009 and 2015. It includes the Tasking Event-B approach; and also code generation for Functional Mock-up Units, for use with the Functional Mock-up Interface (FMI) standard. Tasking Event-B is an extension to Event-B, for defining concurrent systems sharing data, for details see the Tasking Event-B Overview page.

Other code generation approaches that are available for Event-B include:

  • EventB2Java generates JML-specified Java implementations of Event-B models. Contributions by Néstor Cataño, Tim Wahls, Camilo Rueda and Víctor Rivera.
  • EventB2JML translates Event-B machines to JML-specified Java abstract classes. Contributions by Néstor Cataño, Tim Wahls, Camilo Rueda and Víctor Rivera.
  • EventB2Dafny translates Event-B proof-obligations into the input language of Dafny. Developed by Néstor Cataño.
  • EventB2SQL translates Event-B machines to Java implementations that make the state of a machine persistent by storing it in a database.
  • EB2ALL (Beta Version) supports automatic code generation from Event-B to C, C++, Java and C#.
  • B2C translates Event-B models to C source code, which may then be compiled using external C development tools.
  • EHDL The plug-in enables VHDL code generation from formal Event-B models automatically.

Code Generation for Co-simulation using FMI - Rodin 2.8

7th November 2014

For the ADVANCE project we have added the ability to generate C code from Event-B component diagrams. We target a particular style of C, which is tailored for use with ADVANCE's Functional Mock-up Interface (FMI) approach. To generate code, a component from a component diagram is selected. The code generator translates to C using a template, and has a facility for packaging the code as a functional mock-up unit (FMU). The FMU can then be used in place of the Event-B component in the diagram for subsequent simulation. The generated C code can also be used to compile code to be used in the deployed product.

The FMU C translation code must be built from the following sources:

Code generation sources reside at:

Sources specifically for generating the FMU C and packaging it, are at: with

The templates feature. .

Code generation plug-ins have dependencies on ProB2, which at this time, is still under development; and Component Diagrams

Code Generation Feature - Version 0.2.5 for Rodin 2.8

29 August 2013

A new version of the Code Generation Plug-in is available. The tool has been updated to accommodate changes made to its plug-in dependencies. It has improved translators for generating Java code, including setting up the project with a Java Nature and Java builder. The Java Development Tool-kit (JDT) is required if you wish to make use of these facilities. We have also added automatic flattening of invariants, and events; and we automatically infer typing annotations and parameter directions. Therefore, a developer has to perform fewer steps to generate code from an appropriately constructed model.

The following information may be of use:

  • A Tasking Event-B Overview.
  • Generating code using state-machine diagrams.
  • The use of Theories in Code Generation.
    • Example Theories can be found in MathExtension the Git repository, or clone this.
  • A tutorial showing an example of specification, refinement, decomposition, Tasking Event-B, and theories for code generation can be found here.
    • The models used in the tutorial are available from the Git repository or clone this.
  • The sources for this version are available here SVN
  • The lastest code generator source is available here: SVN

Code Generation Feature - Version 0.2.3 for Rodin 2.7

04 Dec 2012. Update

We discovered a compatibility issue wrt the machine-generated Event-B model of the implementation. This occurs when Event-B is generated using the pop-up menu: Code Generation/Create Event-B build errors. The adjacent menu item (remove generated Event-B) can remove the Event-B that causes the errors.

The error occurs due to recently introduced static checks; these flag duplicate variable names in composed (but separate) machines as an error. We plan to release a fix for this problem in due course.

The problem does not effect the generation of code, once the errors have been fixed.

Example Projects and Theories, as below.

Code Generation Feature - Version 0.2.3 for Rodin 2.5

We released the latest Code generation Feature on 30th May 2012.

New features include:

  • Code generation from state-machine diagrams.
  • Improved static checking.

We have also provided some details of the use of Theories in code generation, from the previous version.

Updated Examples etc. are available:

  • Tutorial, and example, projects are available from the Examples directory: SVN.
  • Test projects are also available from the Examples directory SVN.
  • Sources (will be) available at: SVN
  • Example Theories at: SVN

Code Generation Feature - Version 0.2.2 for Rodin 2.4

We released V0.2.2 on 22-03-2012. The main changes, to the interface, and translation from theories are described below:

  • Tasking Event-B is now integrated with the Event-B Editors.
  • We have the ability to translate to C, Java, etc. in addition to Ada source code.
  • We use theories to define translations of the Event-B mathematical language (Theories for Ada, Java and C are supplied).
  • We use the theory plug-in as a mechanism for defining new data types , and the translations to target data types.
  • The translator is extensible.
  • Minimal use is made of the EMF tree editor in Rose.

To install v0.2.2:

  • Access the main Rodin Update Site. In Eclispe click on Help/Install new Software. Find the Rodin update site from the list. In Utilities add Code Generation.

The approach makes use of the following, which should be installed if the features are required by the user for editing:

  • Model Decomposition: Download from the main Rodin Update Site, in the Decomposition section.
  • Shared Event Composition: Download from the main Rodin Update Site, in the Decomposition section.
  • Theory Plug-in: Download from the main Rodin Update Site, in the Modelling Extensions section.

Examples available at:

  • Tutorial, and example, projects are available from the Examples directory: SVN.
  • Test projects are also available from the Examples directory SVN.
  • Sources at: SVN
  • Example Theories at: SVN

Code Generation Feature - Version 0.2.1 for Rodin 2.3

Contains Bug Fixes for previous release. 14-12-2011

Code Generation Feature - Version 0.2.0 for Rodin 2.3

We released a new version of the code generator on 30-11-2011, and updated documentation.

Changes to the Tooling and Approach

The main changes are:

  • The code generators have been completely re-written. The translators are now implemented in Java, i.e. there is no longer a dependence on the Epsilon tool set. This was undertaken for code maintenance reasons.
  • Tasking Event-B is now integrated with the Event-B explorer.
  • The Rose Editor is used for editing the Tasking Event-B, and
  • a text-based editor is provided, using the Rose extension, for editing the TaskBody. This feature has been added to address some of the usability concerns. It also overcomes the 'problem' experienced with duplicate event names in a development, since the parser-builder that has been implemented automatically selects the correct event.
  • The EMF tree editor in Rose is only used minimally; we plan enhancements to further reduce its use.
  • Composed machines are used to store event 'synchronizations'; these are generated automatically during the decomposition process. This reduces the amount of typing in the TaskBody editor, since we no longer need to specify both local and remote (synchronizing) events.
  • The code generation approach is now extensible; new target language constructs can be added using the Eclipse extension mechanism.
  • The translation of target's mathematical language is now specified in the theory plug-in. This improves clarity since the the translation from source to target is achieved by specifying pattern matching rules. Extensibility is also improved; the theory plug-in is used to specify new data-types, and how they are implemented.
  • Translated code is deposited in a directory in the appropriate files. An Ada project file is generated for use with AdaCore's GPS workbench. Eventually this could be enabled/disabled in a preferences dialog box.
  • The Tasking Event-B to Event-B translator is now properly integrated. Control variable updates to the Event-B model are made in a similar way to the equivalent updates in the state-machine plug-in. The additional elements are added to the Event-B model and marked as 'generated'. This prevents users from manually modifying them, and allows them to be removed through a menu choice.
Changes to the Documentation

The following Pages have been updated:


  • Add addressed variables (for direct read/write access to memory)
  • Flattening of composed machines/implementation machines.
  • Interrupts

Sensing and Actuating for Tasking Event-B

Version 0.1.5. Sensing and actuating events, and an Environ Machine have been added to allow simulation of the environment and implementation using memory mapped IO.

  • The new v0.1.5 feature is available from the Rodin Update Site, it resides in the Utilities Category.
  • Select 'the Epsilon Core (Incubation)' component, this is the only component that is required for Tasking Event-B.

A new Code Generation Tutorial has been produced, that makes use of these new features. There is an explanation of the heating controller, upon which it is based, here.

The example/tutorial projects, and also and a Bundled Windows 7 version, are available in the Deploy E-Prints archive or Examples SVN site.

The Code Generation Demonstrator for Rodin 2.1.x

Released 24 January 2011.

The Rodin 2.1.x compatible code generation demonstrator plug-ins have been released into the Rodin Sourceforge repository at: 

The update-site is available through the Rodin update site in the Utilities category.

The code generation tutorial examples are available for download at:

The code generation plug-in relies on the Epsilon tool suite. Install Epsilon manually, since the automatic install utility does not seem to work for this feature. We currently use the Epsilon interim update site available at:

Select 'the Epsilon Core (Incubation)' component, this is the only component that is required for Tasking Event-B.

Latest Developments

  • Demonstrator plug-in feature version 0.1.0
    • for Rodin 2.1.x version is available.
  • The Code Generation feature consists of,
    • a tasking Development Generator.
    • a tasking Development Editor (Based on an EMF Tree Editor).
    • a translator, from Tasking Development to Common Language Model (IL1).
    • a translator, from the Tasking Development to Event-B model of the implementation.
    • a pretty-printer for the Tasking Development.
    • a pretty-printer for Common Language Model, which generates Ada Source Code.
  • A tutorial is available Code Generation Tutorial
    • Step 1 - Create the tasking development.
    • Step 2 - Add annotations.
    • Step 3 - Invoke translators.

Ongoing Work

  • Full Rodin Integration
  • Sensed Variables
  • Branching in Shared Machines

Future Work

  • Support for Interrupts.
  • Richer DataTypes.
  • Accommodation of duplicate event names in tasking developments.


  • In the plug-in we define several meta-models:
    • CompositeControl: for the control flow (algorithmic) constructs such as branch, loop and sequence etc. These constructs may be used in the specification of either sequential or concurrent systems.
    • Tasking Meta-model: defines the tasking model where we attach tasking specific details, such as task priority, task type. The tasking structures provide the ability to define single tasking or multi-tasking (concurrent) systems. We make use of the composite control plug-in to specify the flow of control.
    • Common Language (IL1) Meta-model: defines an abstraction of common programming language constructs for use in translations to implementations.

Translation Rules

  • Tasking to IL1/Event-B translation rules [[1]]

The Code Generation Demonstrator for Rodin 1.3.x

First release: 30 November 2010.

available from:

The zip file contains a windows XP bundle, and a Windows V7 bundle. Alternatively, if you wish to build using an update-site, this is also included in the zip file, along with some notes on installation. However, note that the demonstrator tool is only compatible with Rodin 1.3.

A simple shared buffer example is provided. This will form the basis of a tutorial (which is work in progress). The WindowsBundles directory contains a Rodin 1.3.1 platform with the Code Generation plug-ins, together with a patch plug-in. The patch plug-in is required to correct an inconsistency in the org.eventb.emf.persistence plug-in. For the bundles, simply extract the appropriate zip file into a directory and run the rodin.exe. The plug-ins are pre-installed - the only configuration necessary may be to switch workspace to <installPath>\rodin1.3bWin7\workspace. When using the update-site the example projects, and the project forming the basis of a simple tutorial, are provided in the accompanying zip file. These should be imported manually.

Mac users - no bundled version available at present, but use the update site in the 'advanced' folder.

A step-by-step Code Generation Tutorial is available

About the Initial Release

The Code Generation (CG) Feature in the initial release is a demonstration tool; a proof of concept, rather than a prototype. The tool has no static checker and, therefore, there will be a heavy reliance on docs and dialogue to facilitate exploration of the tools and concepts.

Source Code

The sources are available from,

Note - I used Eclipse 3.5 Galileo, and you will need to install (or have sources from) Epsilon's interim update site. There is also dependency on Camille v2.0.0