B.Eng. Iran (1970), M.Sc. Toronto (1972), Ph.D. Toronto (1976)

For more information on specific projects, please see the LCSR home page.

• Object-oriented programming
• Performance issues
• Garbage collection
• Garbage collection in Java
• Concurrent object-oriented languages

Technical Report CS-2000-04, Department of Computer Science, York University.

Proceedings of 2001 ACM SIGPLAN Conference on Object-Oriented Programming, Systems, and Applications (OOPSLA'2001), Tampa Florida, USA, October 2001, pp. 353-366..

2001Proceedings of CAS (CASCON) Conference,IBM Canada Laboratory, 2001.

(This paper appeared in the Proceedings of 13th Annual International Symposium on High Performance Systems and Applications, June 13 - 16, 1999, Kingston, Ontario.

(This paper appeared in USENIX's Conference on Object-Oriented Technologies and Systems, COOTS'96, June 1996, pp. 233-240. Also in Computing Systems, Vol. 9 No. 4, Fall 1996, pp. 313-329.)

ABC++ is a portable object-oriented type-safe class library for concurrent programming. It supports active objects, synchronous and asynchronous object interactions, and object-based shared regions on both shared- and distributed-memory parallel computers. ABC++ is written in, and compatible with, standard C++: no language extensions or pre-processors are used. This paper focuses on the use of an object-oriented technique called smart messages to support object interactions. Smart messages demonstrate the effectiveness of object-oriented programming in encapsulating low-level details of concurrency and in improving software portability.

(This paper appeared in IBM Systems Journal, Vol. 34, No. 1, 1995, pp. 120-136.)

Many attempts have been made to add concurrency to C++, but much of the work has not exploited the power of C++, and often extensive compiler extensions are made. This paper shows how the object-oriented facilities of C++ are powerful enough to encapsulate concurrency creation and control. We have developed a concurrent C++-based system which we call ABC++. We show how we can provide, with a standard compiler, almost all of the functionality offered by a new or extended language. Active objects, object distribution, selective method acceptance, and synchronous and asynchronous object interaction are supported. Concurrency control and synchronization are encapsulated at the active object level. The goal of ABC++ is to allow its users to write concurrent programs without dealing with explicit synchronization and mutual exclusion constructs, and with as few restrictions on the use of C++ as possible. ABC++ can be implemented on either a shared memory multiprocessor or a cluster of homogeneous workstations. It is presently implemented on a network of RISC System/6000s and on IBM's Scalable POWERparallel Systems 1 (SP1).

Many attempts have been made in adding concurrency to \C++ either by extending the language or through the use of a class library. This paper reviews and analyzes some of the concurrent \C++-based systems. We study the various approaches taken by these systems in adding concurrency to \C++ and how these approaches interact with the object-oriented paradigm.