Concurrent Object-Oriented Programming

Bertrand Meyer and Patrick Eugster, summer semester 2005

Announcements

14 June 2005: Project topic has changed. No GUI is required anymore! Check this out!.

7 June 2005: No lecture today. We will have a two-hour exercise session instead. The scoop2scoopli tool will be presented.

6 May 2005: The solution of the Santa Claus problem by Giovanni Azua is available online.

27 April 2005: Read the introduction to EiffelStudio.

26 April 2005: See papers on the Santa Claus problem and its solutions: in Java and in Polyphonic C#

25 April 2005: Exercise sheet for exercise 2 is available online.

25 April 2005: Mutex/monitor examples from exercises can be found here.

25 April 2005: Slides for Lecture 3 are available online.

22 April 2005: There will be one hour of lecture on 26 April (it will start at 13:15), followed by two hours of exercises.

22 April 2005: In the concurrency seminar on 26 April (16:15, IFW C42) Klaus Havelund will present his work on "Monitoring programs with Eagle".

12 April 2005: the exercise session is replaced by an additional hour of lecture.

5 April 2005: ROOM CHANGE - all lectures and exercise sessions (until the end of the semester) will be taking place in IFW E42.

4 April 2005: no exercise session on April 5.

17 March 2005:

• Register for the course: Please send an email
  To: concur-course (at) se.inf.ethz.ch
  Subject: Concurrency Course Participant
  Content:
  • Your name.
  • Preferred email address.
  • Status: Diploma/Master student (what semester), PhD student, other.
  • Taking the course for credit or not. 

Description

Title and Code

Concurrent Object-Oriented Programming
Course code: 251-0268-00

Scope

Object technology has interesting potential applications to concurrency, distribution, real-time and Web Services. In practice, a number of obstacles have prevented O-O techniques from repeating in the concurrent world the success they have now achieved in the sequential word. This course explores the connections between the object-oriented and concurrent programming paradigms, discussing the problems that arise in the process of attempting to merge them. It reviews the main existing approaches to concurrent O-O computation, including both widely used libraries for multi-threading in Java and .NET and more theoretical frameworks, with a particular emphasis on the SCOOP model. It also provides some of the formal background for discussing the correctness of concurrent O-O applicatons.

Topics

Overview

• Concurrent and parallel programming
• Distributed programming
• Client-server programming
• Internet, Web Services
• Specific issues of embedded and real-time concurrency

Approaches to concurrent programming

• Notion of process, thread and application domain
• Message passing versus variable sharing
• Data consistency issues
• Enforcing synchronization: semaphores, monitors, barriers, etc.
• Java and .NET multithreading

Formal models of concurrency

• Computation versus observation
• Interesting properties of concurrent programs
• Concurrent calculi: CSP, Pi-calculus, ...

Concurrency and Object-Orientation

• Language issues
• Processes versus objects
• Synchronizing objects

The SCOOP model

• Processors; handling an object
• Synchronous and asynchronous feature calls
• Design by Contract in a concurrent context
• Separate objects and entities
• Accessing separate objects; validity rules 
• Synchronization: waiting, reserving, preconditions as wait conditions, Wait by Necessity
• Deadlock avoidance
• Interrupting a reservation: duels and priorities
• Mapping the processors to physical resources
• Examples and applications

Extensions and open problems

• Real-time and embedded extensions
• Timing contracts
• Proofs of SCOOP programs

Prerequisites

The course assumes good knowledge of object-oriented principles and programming techniques. Experience with Eiffel and with concurrent programming is helpful but not required.

Objectives

The goal is to provide students with solid knowledge of:

• State-of-the-art concurrent programming models, languages, and platforms.
• Foundations for reasoning about concurrent and distributed programs.
• Approaches blending object-orientation, distribution, and concurrency.
• Designing applications with concurrent objects.
• Some open issues, like applications to embedded and real-time systems.
• Specific technology:  SCOOP.

Organisation

The course is split into two major parts:

• COOP: a bottom-up, more historical, perspective on concurrent programming. Illustrations are thus made in various programming languages, though Java will be the main focus (Patrick).
• SCOOP: concurrent programming with SCOOP. This will part will take a more top-down approach by illustrating issues related to concurrency through the SCOOP model (Bertrand).

Companion Seminar

Topics in Concurrency, 251-0270-00, Tuesday 16.15 - 17.00 IFW C42.

Schedule

Weekly schedule

• Exercise: Tuesday 13.15 - 14.00, IFW E42
• Lecture:  Tuesday 14.15 - 16.00, IFW E42 

Office hours: Thursday 14.15-16.00, or by appointment, RZ J3

Lectures (Tentative)

Exercises (Tentative)

Grading

Important : No Testat is delivered for the course. The only way to get a grade is to take the written exam and submit the project. This applies regardless of your department or status.

• 65% Project: development of a concurrent application using SCOOP (project description will be announced on 24 May).
• 35% Exam: all presented topics excluding SCOOP. The exam will be held during in the last lecture on June 28.

Textbooks

Gul Agha, Peter Wegner, Akinori Yonezawa (Editors): Research Directions in Concurrent Object-Oriented Programming. MIT Press, 1993.

Gregory R. Andrews:Foundations of Multithreaded, Parallel, and Distributed Programming. Pearson Addison Wesley, 1999.

Mordechai Ben-Ari: Principles of Concurrent and Distributed Programming. Prentice Hall, 1990.

Howard Bowman and John Derrick (Editors): Formal methods for distributed processing: a survey of object-oriented approaches. Cambridge University Press, 2001.

Bertrand Meyer: Object Oriented Software Construction, second edition, Chapter 30, Prentice Hall, 1997.

Contacts

• Send all email relative to this course to concur-course (at) se.inf.ethz.ch. It will reach the professor and the assistants. Do not use their personal addresses.
• Contact assistant for the course: Piotr Nienaltowski (http://se.inf.ethz.ch/people/nienaltowski, office RZ J3)

Last modified: 07.06.2005 by Piotr Nienaltowski