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Abstract An essential motivation behind concurrent object-oriented programming is to exploit the software reuse potential of object-oriented features in the development of concurrent systems. Early attempts to introduce concurrency to object-oriented languages uncovered interferences between object-oriented and concurrency features that limited the extent to which the benefits of object-oriented programming could be realized for developing concurrent systems. This has fostered considerable research into languages and approaches aiming at a graceful integration of object-oriented and concurrent programming. We will examine the issues underlying concurrent object-oriented programming, examine and compare how different approaches for language design address these issues. Although it is not our intention to make an exhaustive survey of concurrent object-oriented languages, we provide a broad coverage of the research in the area. Considerable research activity in the past few years has concentrated on the design of concurrent

/Kurzfassung 3/4 Chapter 1 Introduction and Overview The Hermes System 6 Reading this Thesis 8 Chapter 2 Extending the Oberon System Introducing Concurrency 9 Programming Primitives 11 Integration of Concurrency into the Oberon System 18 Enhancing the Network Support of Oberon 22 Chapter 3 A General Data Transfer Facility On Transfer of Data Structures 27 The IO Framework 29 Default Component Implementations 34 Related Work 39 Chapter 4 The Message Passing Facility Towards an Abstract Message Model 43 The Communication Primitives 44 Message Transmission 49 Related Work 56 Chapter 5 Remote Objects An Event-Oriented Execution Model 61 Installation 62 Sharing and Garbage Collection 64 Implementing Remote Objects 68 Handler Execution 71 Resource Control 73 Related Work 74 Chapter 6 Applications Reliable and Totally Ordered Broadcasting 77 Support for Remote Computations 84 Chapter 7 Conclusions 89 Appendix System Size and Performance Figures 93 References 3...

Current parallel programming languages support only a narrow range of programming styles; force programmers to bind the specification of parallelism too early in program development; and limit the class of architectures for which they are effective. This paper presents a model for parallel programming based on uniform encapsulation and control, concurrent operations on objects, synchronous invocation with early reply, references to code in an environment, and a copy model of parameters and variables. This simple, coherent model enables programmers to use different styles of programming and to bind parallelism late in program development. In addition, the model may be efficiently implemented on a wide range of multiprocessor architectures. 1 Introduction Current imperative languages for parallel programming tend to provide separate facilities for parallel programming on top of a base sequential model of programming. These facilities typically include a distinct notion of process, monit...