Model checking

• In this course we use the text book Principles of the Spin Model Checker by Ben-Ari.
• The book by Clarke et al. is a standard reference of Model Checking in general.

Logic

• There are many good books on first-order (aka predicate) logic. We recommend, as a good introduction, Logic in Computer Science by Michael Huth and Mark Ryan.
• First-order logic with Java-style types as discussed in the last part of the course is described in depth in Chapter 2 of in Verification of Object-Oriented Software: The KeY Approach.

UML

The most basic notions of UML will suffice in this course. It is enough to understand the essentials of class and object diagrams.

• The Object Management Grup (OMG) is an industrial consortium responsible for standards development in object-oriented computing. In particular they maintain UML, where all kinds of UML/OCL documents can be found.
• If you need an introduction or refresher on UML, then Martin Fowlers's UML Distilled is strongly recommended. Still the best basic text on UML (plus a lot of general wisdom on OOP). The 3rd edition is compliant with UML 2.0.

Java Card

• The Java Card 2.2.1 API as supported by KeY can be found here
• Sun's portal for Java technology, and for Java Card technology
• If you need a refresher on Java, then Jia's Object Oriented Software Development Using Java 2/e is warmly recommended.
• Every computer professional dealing with Java needs to own the Java Language Specification and the Java Programming Language, but that goes without saying.

Web-interfaces

This year is the first year we present an online interface to some of the tools used in the course, to avoid installation problems.

• Notes on saving
  • The web-interface does not save your files. To save your progress, copy the content of the editor into a file local on your machine (or save it by pressing Ctrl+S)!
• Spin
  • In the top-left corner you find a collection of examples and Promela files used in the course, as well as a cheat sheet to the most used Promela syntax.
  • You can create a file by either choosing one from the collection of examples, or by clicking the (+) button above the editor.
  • You can press Ctrl+S in an opened tab to save that tab to your local machine.
  • The control panel on the right allows you to run simulations and verifications on the file that is in the currently opened tab (programs with multiple files are not supported).
  • The first group of options displays events that are printed during simulations and guided runs. Note that if 'Statements' is not selected almost no information will be printed. These options apply to both the simulation as well as running the generated trail of verification.
  • It is recommended to use the 'Stop after ...' option when running simulations that print all statements, otherwise your browser might take a long time for displaying the output.
  • For verification, select the right mode (Safety, Acceptance / Liveness, Non-progress) and specify the name of the named LTL formula in the currently opened Promela file that you want to verify. If a counter-example is found and 'Run generated trail' is selected the trail of the counter-example is printed at the bottom of the output.
  • The timeout for simulations is set to 1 second; for verification it is set to 30 seconds.
  • The official web-interface to Spin is located here, in case of high traffic an alternative installment can be found here.
• OpenJML
  • In the top-left corner you find a collection of example Java files and those used in the course.
  • You can create a file by either choosing one from the collection of examples, or by clicking the (+) button above the editor.
  • By clicking the 'Syntax' button OpenJML is run to check that your JML annotations use correct syntax.
  • By clicking the 'ESC' button OpenJML runs an Extended Static Check, using Yices 2 as its back-end, to statically find violations of your JML specification.
  • You can hover over the warning / error markers on the left-hand side to see the output of OpenJML.
  • The official web-interface to OpenJML is located here, in case of high traffic an alternative installment can be found here.

Promela, Spin and jSpin

• We have created an online interface to the Spin model checker to avoid installation problems.
• We compiled a list of instructions on installing Spin and jSpin on your own computer or using it at the remote Chalmers servers here.
• In case our instructions do not work, you should use the official instructions for Spin, jSpin and SpinSpider.
• The handy Ben-Ari's Spin Reference card.
• The home page of Promela/Spin.
• The definitive reference for Promela and Spin is The Spin Model Checker by Holzmann. It contains the full theoretical background.
• Promela mode for Emacs
• Eclipse Plug-in for Spin

OpenJML

• We have created an online interface to OpenJML (including static checking with Yices2) to avoid installation problems.
• The latest version of OpenJML can be found on their website (direct link here).
• Within the directory where you extracted openjml.jar, run the command

  java -Xbootclasspath/p:openjml.jar -jar openjml.jar -noInternalSpecs path_to_file

• If you cannot run java 1.7, we have a local copy of an older release that still supported 1.6 here.
• OpenJML allows you to compile to a bytecode (.class) file with inlined run-time assertion checks on your invariants, pre- and post-conditions. Try this for example with this file. Compile using:

  java -Xbootclasspath/p:openjml.jar -jar openjml.jar -rac -noInternalSpecs path_to_file

  (note the extra -rac flag). For Java 1.6, use instead:

  java -Xbootclasspath/p:openjml.jar -jar openjml.jar -rac -source 1.6 -target 1.6 -noInternalSpecs path_to_file

  Then run the program with:

  java -classpath ':*' JMLTest 12

  Where 12 is the input to the program. You can try different inputs and see how the assertions can be triggered.

KeY

• The version used in this course is available via webstart here.

  Note on versions: the KeY system's target language for verification is not Java, but Java Card. Java Card is Sun's Java dialect intended to run on smart cards and other embedded systems. Its syntax and API are mostly a restriction of Java (the exact differences will be explained in the lectures). This means that Java programs that obey the restrictions of Java Card can be verified with KeY as well. In fact, all the programs discussed in this course are at the same time Java and Java Card programs. The latest version of Java is 1.6, and the latest version of Java Card is 2.2.2.

  The KeY system supports Java Card 2.2.1, but the differences between 2.2.1 and 2.2.2 lie only in the API. Java Card has no generic types, therefore, Java Card programs syntactically conform to Java 1.4 (up to the API, of course). In particular, from the Java Card API we will only use java.lang, which is a (very small) subset of all Java SDK2 APIs.

• There is a book on the KeY system called Verification of Object-Oriented Software: The KeY Approach. You can access the online version from a Chalmers account. Navigate to Chalmers Library, E-Books, Lecture Notes in Computer Science. Chapter 1 in the book gives a general introduction in the philosophy behind KeY. Chapter 10 is an introduction into the usage of the system. See also the KeY project website.
• KeY Quicktour is available at the KeY download page.
• Verifying Object-Orient Programs with KeY: A Tutorial, an article that contains an advanced example for specification in JML and verification with KeY.
  See also the corresponding source files (click 'updated version').

• Formal Methods Humor
• Formal Methods Education Resources
• Formal Methods in Wikipedia