957 resultados para Java applets


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Over the years the use of application frameworks designed for the View and Controller layers of MVC architectural pattern adapted to web applications has become very popular. These frameworks are classified into Actions Oriented and Components Oriented , according to the solution strategy adopted by the tools. The choice of such strategy leads the system architecture design to acquire non-functional characteristics caused by the way the framework influences the developer to implement the system. The components reusability is one of those characteristics and plays a very important role for development activities such as system evolution and maintenance. The work of this dissertation consists to analyze of how the reusability could be influenced by the Web frameworks usage. To accomplish this, small academic management applications were developed using the latest versions of Apache Struts and JavaServer Faces frameworks, the main representatives of Java plataform Web frameworks of. For this assessment was used a software quality model that associates internal attributes, which can be measured objectively, to the characteristics in question. These attributes and metrics defined for the model were based on some work related discussed in the document

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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With the increasing complexity of software systems, there is also an increased concern about its faults. These faults can cause financial losses and even loss of life. Therefore, we propose in this paper the minimization of faults in software by using formally specified tests. The combination of testing and formal specifications is gaining strength in searches mainly through the MBT (Model-Based Testing). The development of software from formal specifications, when the whole process of refinement is done rigorously, ensures that what is specified in the application will be implemented. Thus, the implementation generated from these specifications would accurately depict what was specified. But not always the specification is refined to the level of implementation and code generation, and in these cases the tests generated from the specification tend to find fault. Additionally, the generation of so-called "invalid tests", ie tests that exercise the application scenarios that were not addressed in the specification, complements more significantly the formal development process. Therefore, this paper proposes a method for generating tests from B formal specifications. This method was structured in pseudo-code. The method is based on the systematization of the techniques of black box testing of boundary value analysis, equivalence partitioning, as well as the technique of orthogonal pairs. The method was applied to a B specification and B test machines that generate test cases independent of implementation language were generated. Aiming to validate the method, test cases were transformed manually in JUnit test cases and the application, created from the B specification and developed in Java, was tested. Faults were found with the execution of the JUnit test cases

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The use of middleware technology in various types of systems, in order to abstract low-level details related to the distribution of application logic, is increasingly common. Among several systems that can be benefited from using these components, we highlight the distributed systems, where it is necessary to allow communications between software components located on different physical machines. An important issue related to the communication between distributed components is the provision of mechanisms for managing the quality of service. This work presents a metamodel for modeling middlewares based on components in order to provide to an application the abstraction of a communication between components involved in a data stream, regardless their location. Another feature of the metamodel is the possibility of self-adaptation related to the communication mechanism, either by updating the values of its configuration parameters, or by its replacement by another mechanism, in case of the restrictions of quality of service specified are not being guaranteed. In this respect, it is planned the monitoring of the communication state (application of techniques like feedback control loop), analyzing performance metrics related. The paradigm of Model Driven Development was used to generate the implementation of a middleware that will serve as proof of concept of the metamodel, and the configuration and reconfiguration policies related to the dynamic adaptation processes. In this sense was defined the metamodel associated to the process of a communication configuration. The MDD application also corresponds to the definition of the following transformations: the architectural model of the middleware in Java code, and the configuration model to XML

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Using formal methods, the developer can increase software s trustiness and correctness. Furthermore, the developer can concentrate in the functional requirements of the software. However, there are many resistance in adopting this software development approach. The main reason is the scarcity of adequate, easy to use, and useful tools. Developers typically write code and test it. These tests usually consist of executing the program and checking its output against its requirements. This, however, is not always an exhaustive discipline. On the other side, using formal methods one might be able to investigate the system s properties further. Unfortunately, specification languages do not always have tools like animators or simulators, and sometimes there are no friendly Graphical User Interfaces. On the other hand, specification languages usually have a compiler which normally generates a Labeled Transition System (LTS). This work proposes an application that provides graphical animation for formal specifications using the LTS as input. The application initially supports the languages B, CSP, and Z. However, using a LTS in a specified XML format, it is possible to animate further languages. Additionally, the tool provides traces visualization, the choices the user did, in a graphical tree. The intention is to improve the comprehension of a specification by providing information about errors and animating it, as the developers do for programming languages, such as Java and C++.

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The Exception Handling (EH) is a widely used mechanism for building robust systems. In Software Product Line (SPL) context it is not different. As EH mechanisms are embedded in most of mainstream programming languages (like Java, C# and C++), we can find exception signalers and handlers spread over code assets associated to common and variable SPL features. When exception signalers and handlers are added to an SPL in an unplanned way, one of the possible consequences is the generation of faulty family instances (i.e., instances on which common or variable features signal exceptions that are mistakenly caught inside the system). In this context, some questions arise: How exceptions flow between the optional and alternative features an LPS? Aiming at providing answers to these questions, this master thesis conducted an exploratory study, based on code inspection and static analysis code, whose goal was to categorize the main ways which exceptions flow in LPSs. To support the study, we developed an static analysis tool called PLEA (Product Line Exception Analyzer) that calculates the exceptional flows of LPSs, and categorize these flows according to the features associated with handlers and signalers. Preliminary results showed that some types of exceptional flows have more potential to yield failures in exceptional behavior of SLPs

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The visualization of three-dimensional(3D)images is increasigly being sed in the area of medicine, helping physicians diagnose desease. the advances achived in scaners esed for acquisition of these 3d exames, such as computerized tumography(CT) and Magnetic Resonance imaging (MRI), enable the generation of images with higher resolutions, thus, generating files with much larger sizes. Currently, the images of computationally expensive one, and demanding the use of a righ and computer for such task. The direct remote acess of these images thruogh the internet is not efficient also, since all images have to be trasferred to the user´s equipment before the 3D visualization process ca start. with these problems in mind, this work proposes and analyses a solution for the remote redering of 3D medical images, called Remote Rendering (RR3D). In RR3D, the whole hedering process is pefomed a server or a cluster of servers, with high computational power, and only the resulting image is tranferred to the client, still allowing the client to peform operations such as rotations, zoom, etc. the solution was developed using web services written in java and an architecture that uses the scientific visualization packcage paraview, the framework paraviewWeb and the PACS server DCM4CHEE.The solution was tested with two scenarios where the rendering process was performed by a sever with graphics hadwere (GPU) and by a server without GPUs. In the scenarios without GPUs, the soluction was executed in parallel with several number of cores (processing units)dedicated to it. In order to compare our solution to order medical visualization application, a third scenario was esed in the rendering process, was done locally. In all tree scenarios, the solution was tested for different network speeds. The solution solved satisfactorily the problem with the delay in the transfer of the DICOM files, while alowing the use of low and computers as client for visualizing the exams even, tablets and smart phones

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New programming language paradigms have commonly been tested and eventually incorporated into hardware description languages. Recently, aspect-oriented programming (AOP) has shown successful in improving the modularity of object-oriented and structured languages such Java, C++ and C. Thus, one can expect that, using AOP, one can improve the understanding of the hardware systems under design, as well as make its components more reusable and easier to maintain. We apply AOP in applications developed using the SystemC library. Several examples will be presented illustrating how to combine AOP and SystemC. During the presentation of these examples, the benefits of this new approach will also be discussed

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O domínio alvo deste trabalho são os sistemas colaborativos distribuídos onde o foco está na troca dê mensagens entre usuários remotamente distribuídos. Nestes sistemas, há a necessidade das mensagens possuírem conteúdo multimídia e poderem ser entregues tanto a um usuário específico quanto a um grupo ou grupos de usuários. O objetivo deste trabalho é desenvolver um framework que facilite: a construção desse tipo de sistymas e diminua o tempo gasto com desenvolvimento através da técnica de reuso. Este trabalho apresenta o N2N Framework - Uma plataforma para desenvolvimento de Sistemas Colaborativos Distribuídos. O Framework foi concebido através da análise do comportamento de aplicações com características de multimídias colaborativas, como ambientes virtuais multi-usuários, chats, enquetes, e torcidas virtuais. O Framework foi implementado usando-se a plataforma Java. O N2N Framework facilita o design e implementação de sistemas colaborativos distribuídos, implementando a entrega das mensagens, e direcionando o desenvolvedor de aplicações para a preocupação com implementação de suas mensagens específicas e o processamento que delas decorre

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Checking the conformity between implementation and design rules in a system is an important activity to try to ensure that no degradation occurs between architectural patterns defined for the system and what is actually implemented in the source code. Especially in the case of systems which require a high level of reliability is important to define specific design rules for exceptional behavior. Such rules describe how exceptions should flow through the system by defining what elements are responsible for catching exceptions thrown by other system elements. However, current approaches to automatically check design rules do not provide suitable mechanisms to define and verify design rules related to the exception handling policy of applications. This paper proposes a practical approach to preserve the exceptional behavior of an application or family of applications, based on the definition and runtime automatic checking of design rules for exception handling of systems developed in Java or AspectJ. To support this approach was developed, in the context of this work, a tool called VITTAE (Verification and Information Tool to Analyze Exceptions) that extends the JUnit framework and allows automating test activities to exceptional design rules. We conducted a case study with the primary objective of evaluating the effectiveness of the proposed approach on a software product line. Besides this, an experiment was conducted that aimed to realize a comparative analysis between the proposed approach and an approach based on a tool called JUnitE, which also proposes to test the exception handling code using JUnit tests. The results showed how the exception handling design rules evolve along different versions of a system and that VITTAE can aid in the detection of defects in exception handling code

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Web services are software accessible via the Internet that provide functionality to be used by applications. Today, it is natural to reuse third-party services to compose new services. This process of composition can occur in two styles, called orchestration and choreography. A choreography represents a collaboration between services which know their partners in the composition, to achieve the service s desired functionality. On the other hand, an orchestration have a central process (the orchestrator) that coordinates all application operations. Our work is placed in this latter context, by proposing an abstract model for running service orchestrations. For this purpose, a graph reduction machine will be defined for the implementation of service orchestrations specified in a variant of the PEWS composition language. Moreover, a prototype of this machine (in Java) is built as a proof of concept

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The main goal of Regression Test (RT) is to reuse the test suite of the latest version of a software in its current version, in order to maximize the value of the tests already developed and ensure that old features continue working after the new changes. Even with reuse, it is common that not all tests need to be executed again. Because of that, it is encouraged to use Regression Tests Selection (RTS) techniques, which aims to select from all tests, only those that reveal faults, this reduces costs and makes this an interesting practice for the testing teams. Several recent research works evaluate the quality of the selections performed by RTS techniques, identifying which one presents the best results, measured by metrics such as inclusion and precision. The RTS techniques should seek in the System Under Test (SUT) for tests that reveal faults. However, because this is a problem without a viable solution, they alternatively seek for tests that reveal changes, where faults may occur. Nevertheless, these changes may modify the execution flow of the algorithm itself, leading some tests no longer exercise the same stretch. In this context, this dissertation investigates whether changes performed in a SUT would affect the quality of the selection of tests performed by an RTS, if so, which features the changes present which cause errors, leading the RTS to include or exclude tests wrongly. For this purpose, a tool was developed using the Java language to automate the measurement of inclusion and precision averages achieved by a regression test selection technique for a particular feature of change. In order to validate this tool, an empirical study was conducted to evaluate the RTS technique Pythia, based on textual differencing, on a large web information system, analyzing the feature of types of tasks performed to evolve the SUT

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Control and automation of residential environments domotics is emerging area of computing application. The development of computational systems for domotics is complex, due to the diversity of potential users, and because it is immerse in a context of emotional relationships and familiar construction. Currently, the focus of the development of this kind of system is directed, mainly, to physical and technological aspects. Due to the fact, gestural interaction in the present research is investigated under the view of Human-Computer Interaction (HCI). First, we approach the subject through the construction of a conceptual framework for discussion of challenges from the area, integrated to the dimensions: people, interaction mode and domotics. A further analysis of the domain is accomplished using the theoretical-methodological referential of Organizational Semiotics. After, we define recommendations to the diversity that base/inspire the inclusive design, guided by physical, perceptual and cognitive abilities, which aim to better represent the concerned diversity. Although developers have the support of gestural recognition technologies that help a faster development, these professionals face another difficulty by not restricting the gestural commands of the application to the standard gestures provided by development frameworks. Therefore, an abstraction of the gestural interaction was idealized through a formalization, described syntactically by construction blocks that originates a grammar of the gestural interaction and, semantically, approached under the view of the residential system. So, we define a set of metrics grounded in the recommendations that are described with information from the preestablished grammar, and still, we conceive and implement in Java, under the foundation of this grammar, a residential system based on gestural interaction for usage with Microsoft Kinect. Lastly, we accomplish an experiment with potential end users of the system, aiming to better analyze the research results

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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A lesion nematode population infecting citrus in the state of São Paulo, Brazil is described and named Pratylenchus jaehni sp. n. Biological, molecular and morphological characteristics of this new species are compared with those of the morphologically similar P. coffeae and P. loosi. Results of mating experiments showed that R jaehni is reproductively isolated from P coffeae. Molecular (D2/D3 DNA sequences) dissimilarities among P. jaehni sp, n., P. coffeae and P. loosi were documented in a previous study. The morphology of seven R coffeae populations from tropical America and eastern Java and a P loosi population from Sri Lanka is used for comparison with the morphology of P. jaehni sp. n. Pratylenchus jaehni differs from R coffeae and P. loosi by only a few morphological ;characters of the females. The mean values of stylet length, stylet knob height, and vulva position are smaller (less than or equal to15 vs greater than or equal to15 mum, less than or equal to2.7 vs greater than or equal to2.7 mum, less than or equal to79 vs greater than or equal to79%) than those in P coffeae and P loosi. The tail terminus is usually subhemispherical and smooth in P jaehni sp. n.. whereas it is commonly truncate and indented in most P. coffeae populations and bluntly or finely pointed in P. loosi. Because of the morphological similarities among P. jaehni sp. n., P. coffeae and P. loosi, examination of at least ten specimens is required to obtain a reliable diagnosis based on morphology. Nineteen morphometric parameters for P. jaehni sp. n. and P. coffeae ranged from 0-13% smaller in fixed than in live specimens.