The reflection technique is used by programs that need to examine or modify the runtime behavior of applications in the java Virtual Machine. This is a powerful instrument, but its use should bring some concerns relat...
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ISBN:
(纸本)9783642325472
The reflection technique is used by programs that need to examine or modify the runtime behavior of applications in the java Virtual Machine. This is a powerful instrument, but its use should bring some concerns related to performance overhead, security problems, exposing the private fields-which are not accessible through non-reflective code, losing benefits of compile-time type checking, reflective code being clumsy and verbose. This paper concentrates upon the performance overhead. Tests were made in order to analyze objects creation and method calls using primitive and reference arguments, both by direct and reflective invocation.
Real-time and embedded applications cover an extremely wide variety of domains, each with stringent requirements, including highly precise timing characteristics, small memory footprints, flexible sensor and actuator ...
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Real-time and embedded applications cover an extremely wide variety of domains, each with stringent requirements, including highly precise timing characteristics, small memory footprints, flexible sensor and actuator interfaces, and robust safety characteristics. Processing in such application domains often involves distributed processing in which communication and synchronization and their resulting integration present additional challenges.
We present a high-level survey of state-of-the-art alias analyses for object-oriented programs, based on a years-long effort developing industrial-strength static analyses for java. We first present common variants of...
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As an outcome of a DAAD (German Academic Exchange Service) sub-project started in 2004 and devoted to teaching the java programming language, a joint pool of primarily advanced topics has been created. This teaching m...
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The multi-faceted nature of communication technologies and information management has demanded that supporting systems be highly cohesive and yet loosely coupled. It calls for the systems to be efficiently integrated,...
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ISBN:
(纸本)9781467360531
The multi-faceted nature of communication technologies and information management has demanded that supporting systems be highly cohesive and yet loosely coupled. It calls for the systems to be efficiently integrated, interoperable and highly adaptable to the ever-changing operating landscape. Interoperability among systems becomes difficult, though the emergence of service oriented technologies had provided some form of reprieve. In today's rapidly changing environment, applications such as healthcare applications need to be highly adaptable and versatile. Service Oriented Architecture (SOA) becomes more and more important. The goal-oriented nature of agent, coupled with highly configurable agent actions, makes it very suitable for implementing such systems. In this research, an agent framework is designed and implemented to cater for the applications of agents in service oriented environment. J2EE technology is used for its implementation so as to enable the service oriented nature of the agent. This paper first discusses several design considerations. Then the agents are developed and incorporated using the proposed agent framework.
Hibernate is the most popular ORM framework for java. It is a straightforward and easy-to-use implementation of java Persistence API. However, its simplicity of usage often becomes mischievous to developers and leads ...
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ISBN:
(纸本)9781467344715
Hibernate is the most popular ORM framework for java. It is a straightforward and easy-to-use implementation of java Persistence API. However, its simplicity of usage often becomes mischievous to developers and leads to serious performance issues in Hibernate-based applications. This paper presents live performance antipatterns related to the usage of one-to-many associations in hibernate. These antipatterns focus on the problems of the owning side of collections, the java types and annotations used in mappings, as well as processing of collections. Each antipattern consists of the description of a problem along with a sample code, negative performance consequences, and the recommended solution. Performance is analyzed in terms of the number and complexity of issued database statement. The code samples illustrate how the antipatterns decrease performance and how to implement the mappings to speed up the execution times.
This project's main aim is to detect unbalancing in three phase circuit. We further provide a software simulation in MATLAB to provide solution to this problem. This MATLAB simulation works with selfadapting intel...
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ISBN:
(纸本)9780769551463
This project's main aim is to detect unbalancing in three phase circuit. We further provide a software simulation in MATLAB to provide solution to this problem. This MATLAB simulation works with selfadapting intelligent agent system that would plot real time unbalancing and balancing of the system. In a balance system all phases, of a three phase power system are distributed at 120 degrees in space with respect to each other. In "three phase four wire" systems, no current flows through neutral wire if system is balanced [1]. We have also shown that how by dividing the areas into sub servers of java we can decrease the inconsistency and remove the discrepancies in the whole system thus tackling these uncontrolled conditions of unbalancing.
Modern software systems that play critical roles in society's infrastructures are often required to change at runtime so that they can continuously provide essential services in the dynamic environments they opera...
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ISBN:
(纸本)9783642415326;9783642415333
Modern software systems that play critical roles in society's infrastructures are often required to change at runtime so that they can continuously provide essential services in the dynamic environments they operate in. Updating open, distributed software systems at runtime is very challenging. Using runtime models as an interface for updating software at runtime can help developers manage the complexity of updating software while it is executing. In this work we describe an approach to updating java software at runtime through the use of runtime models consisting of UML class and activity diagrams. Changes to models are turned into changes on java source code, which is then propagated to the runtime system using the javadaptor technology. In particular, the presented approach permits in-the-small software changes, i.e., changes at the code statement level, as opposed to in-the-large changes, i.e., changes at the component level. We present a case study that demonstrates the major aspects of the approach and its use.
A key issue in the development of reliable embedded software is the proper handling of reactive control-flow, which typically involves concurrency. java and its thread concept have only limited provisions for implemen...
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ISBN:
(纸本)9781479921133
A key issue in the development of reliable embedded software is the proper handling of reactive control-flow, which typically involves concurrency. java and its thread concept have only limited provisions for implementing deterministic concurrency. Thus, as has been observed in the past, it is challenging to develop concurrent java programs without any deadlocks or race conditions. To alleviate this situation, the Synchronous java (SJ) approach presented here adopts the key concepts that have been established in the world of synchronous programming for handling reactive control-flow. Thus SJ not only provides deterministic concurrency, but also different variants of deterministic preemption. Furthermore SJ allows concurrent threads to communicate with Esterel-style signals. As a case study for an embedded system usage, we also report on how the SJ concepts have been ported to the ARM-based Lego Mindstorms NXT system.
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