Multi-Threaded Actors

In this paper we introduce a new programming model of multi-threaded actors which feature the parallel processing of their messages. In this model an actor consists of a group of active objects which share a message queue. We provide a formal operational semantics, and a description of a Java-based implementation for the basic programming abstractions describing multi-threaded actors. Finally, we evaluate our proposal by means of an example application.Comment: In Proceedings ICE 2016, arXiv:1608.0313

KLAIM: A Kernel Language for Agents Interaction and Mobility

We investigate the issue of designing a kernel programming language for mobile computing and describe KLAIM, a language that supports a programming paradigm where processes, like data, can be moved from one computing environment to another. The language consists of a core Linda with multiple tuple spaces and of a set of operators for building processes. KLAIM naturally supports programming with explicit localities. Localities are first-class data (they can be manipulated like any other data), but the language provides coordination mechanisms to control the interaction protocols among located processes. The formal operational semantics is useful for discussing the design of the language and provides guidelines for implementations. KLAIM is equipped with a type system that statically checks access rights violations of mobile agents. Types are used to describe the intentions (read, write, execute, etc.) of processes in relation to the various localities. The type system is used to determine the operations that processes want to perform at each locality, and to check whether they comply with the declared intentions and whether they have the necessary rights to perform the intended operations at the specific localities. Via a series of examples, we show that many mobile code programming paradigms can be naturally implemented in our kernel language. We also present a prototype implementaton of KLAIM in Java

Towards Object-Oriented Klaim

Abstract By its own nature, mobile code requires flexibility in order to be adaptive to any execution context it may be run in. In this paper we investigate this flexibility requirement from the design point of view, and propose a solution based on the mixin technique to fulfill it. We also propose an extension of the language K laim with object-oriented features, as an application of this approach

A Mechanized Model of the Theory of Objects

In this paper we present a formalization of Abadi's and Cardelli's theory of ob jects in the interactive theorem prover Isabelle/HOL. Our motivation is to build a mechanized HOL-framework for the analysis of a functional calculus for distributed ob jects. In particular, we present (a) a formal model of ob jects and its operational semantics based on de Bruijn indices (b) a parallel reduction relation for ob jects (c) the proof of confluence for the theory of ob jects reusing Nipkow's HOL-framework for the lambda calculus. We expect this framework to be highly reusable and allow further development and mechanized proofs of various aspects of ob ject theory, e.g., distribution, aspect orientation, typing

A Mechanized Model of the Theory of Objects

In this paper we present a formalization of Abadi's and Cardelli's theory of ob jects in the interactive theorem prover Isabelle/HOL. Our motivation is to build a mechanized HOL-framework for the analysis of a functional calculus for distributed ob jects. In particular, we present (a) a formal model of ob jects and its operational semantics based on de Bruijn indices (b) a parallel reduction relation for ob jects (c) the proof of confluence for the theory of ob jects reusing Nipkow's HOL-framework for the lambda calculus. We expect this framework to be highly reusable and allow further development and mechanized proofs of various aspects of ob ject theory, e.g., distribution, aspect orientation, typing

A mechanized model of the theory of objects

Abstract. In this paper we present a formalization of Abadi's and Cardelli's theory of objects in the interactive theorem prover Isabelle/HOL. Our motivation is to build a mechanized HOL-framework for the analysis of a functional calculus for distributed objects. In particular, we present (a) a formal model of objects and its operational semantics based on de Bruijn indices (b) a parallel reduction relation for objects (c) the proof of confluence for the theory of objects reusing Nipkow's HOL-framework for the lambda calculus. We expect this framework to be highly reusable and allow further development and mechanized proofs of various aspects of object theory, e.g., distribution, aspect orientation, typing

Communication Infrastructure Design for Wide-Area Mobile Computation: Specification in Nomadic Pict

We review an example of wide-area mobile agent applications: video-on-demand, long-lived scientific computation, and collaborative work, and the design of a distributed infrastructure required in each of these applications for location-independent communication. For the latter application, we propose an infrastructure algorithm that assumes two kinds of collaboration: (1) within a group of ``mobile'' individuals, who can communicate frequently using different computers connected to a local-area network (possibly via a wireless medium), and (2) some individuals may also communicate outside their groups using the global network. The algorithm has been specified formally, as an executable encoding in Nomadic Pict. The formal specification is concise but gives enough details to be directly translated by application programmers using their language of choice