1,103,378 research outputs found
Monitoring distributed object and component communication
This thesis presents our work in the area of monitoring distributed software applications (DSAs). We produce three main results: (1) a design approach for building monitoring systems, (2) a design of a system for MOnitoring Distributed Object and Component Communication (MODOCC) behavior in middleware-based applications, and (3) a proof-of-concept implementation of this system
Abstracting object interactions using composition filters
It is generally claimed that object-based models are very suitable for building distributed system architectures since object interactions follow the client-server model. To cope with the complexity of today's distributed systems, however, we think that high-level linguistic mechanisms are needed to effectively structure, abstract and reuse object interactions. For example, the conventional object-oriented model does not provide high-level language mechanisms to model layered system architectures. Moreover, we consider the message passing model of the conventional object-oriented model as being too low-level because it can only specify object interactions that involve two partner objects at a time and its semantics cannot be extended easily. This paper introduces Abstract Communication Types (ACTs), which are objects that abstract interactions among objects. ACTs make it easier to model layered communication architectures, to enforce the invariant behavior among objects, to reduce the complexity of programs by hiding the interaction details in separate modules and to improve reusability through the application of object-oriented principles to ACT classes. We illustrate the concept of ACTs using the composition filters model
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Losing by Expanding: Corralling the Runaway Object
At the time of publication C. Spinuzzi was at the University of Texas at Austin.Third-generation activity theory (3GAT) has become a popular theoretical and methodological framework for writing studies, particularly in technical communication. 3GAT involves identifying an object, a material or problem that is cyclically transformed by collective activity. The object is the linchpin of analysis in the empirical case. Yet the notion of object has expanded methodologically and theoretically over time, making it difficult to reliably bound an empirical case. In response, this article outlines the expansion of the object, diagnoses this expansion, and proposes an alternate approach that constrains the object for case-study research in writing studies.Writin
A type system for components
In modern distributed systems, dynamic reconfiguration, i.e.,
changing at runtime the communication pattern of a program, is chal-
lenging. Generally, it is difficult to guarantee that such modifications will
not disrupt ongoing computations. In a previous paper, a solution to this
problem was proposed by extending the object-oriented language ABS
with a component model allowing the programmer to: i) perform up-
dates on objects by means of communication ports and their rebinding;
and ii) precisely specify when such updates can safely occur in an object
by means of critical sections. However, improper rebind operations could
still occur and lead to runtime errors. The present paper introduces a
type system for this component model that extends the ABS type system
with the notion of ports and a precise analysis that statically enforces
that no object will attempt illegal rebinding
Modular session types for objects
Session types allow communication protocols to be specified
type-theoretically so that protocol implementations can be verified by static
type checking. We extend previous work on session types for distributed
object-oriented languages in three ways. (1) We attach a session type to a
class definition, to specify the possible sequences of method calls. (2) We
allow a session type (protocol) implementation to be modularized, i.e.
partitioned into separately-callable methods. (3) We treat session-typed
communication channels as objects, integrating their session types with the
session types of classes. The result is an elegant unification of communication
channels and their session types, distributed object-oriented programming, and
a form of typestate supporting non-uniform objects, i.e. objects that
dynamically change the set of available methods. We define syntax, operational
se-mantics, a sound type system, and a sound and complete type checking
algorithm for a small distributed class-based object-oriented language with
structural subtyping. Static typing guarantees that both sequences of messages
on channels, and sequences of method calls on objects, conform to
type-theoretic specifications, thus ensuring type-safety. The language includes
expected features of session types, such as delegation, and expected features
of object-oriented programming, such as encapsulation of local state.Comment: Logical Methods in Computer Science (LMCS), International Federation
for Computational Logic, 201
A simple approach to distributed objects in prolog
We present the design of a distributed object system for Prolog, based on adding remote execution and distribution capabilities to a previously existing object system. Remote execution brings RPC into a Prolog system, and its semantics is easy to express in terms of well-known Prolog builtins. The final distributed object design features state mobility and user-transparent network behavior. We sketch an implementation which provides distributed garbage collection and some degree of tolerance to network failures. We provide a preliminary study of the overhead of the communication mechanism for some test cases
ADDICTIONS SUBSTANCE FREE DURING LIFESPAN
The addictions substance free is an umbrella definition comprises internet addiction, sexual addiction, gambling pathological, workholism, videogames and computer addiction. Actually, the technological addictions is frequent in young adolescents. The term Digital Natives indicates the children born in an information system of learning and communication different from that of the generations previous. This temporal range was strongly characterized by growing presence of technological communication toolsin daily life. The effects of hyper-exposition to technological tools tend to create a relational virtuality without a body is born,therefore, already within the family ties and during adolescence he moved to the digital socialization network. The technological object it interacts between the adolescent and the world of peers and adults, becoming the facilitator object that as the psychotropic substance, it conveys new modes of communicatio
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