If the first chapter of the Internet was about the dissemination of information, chapter two is about services. In the past, the Internet strategy of a company was about using a web site for advertising products. Toda...
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If the first chapter of the Internet was about the dissemination of information, chapter two is about services. In the past, the Internet strategy of a company was about using a web site for advertising products. Today the concept of product becomes almost indistinguishable from the concept of service, and the Internet becomes a key component of any type of channel. Electronic marketplaces and e-services are two of the main drivers for the change from chapter one to chapter two for the Internet, both from a business and technology perspective. E-services are about assets made available efficiently over the Internet. Electronic marketplaces are about demand for services being put in contact with the best offer. The two concepts naturally complement each other. The objective of this paper is to introduce the concepts behind both e-services and electronic marketplaces, and to show an example of the use of java as enabling technology. The example focuses on a novel approach to mediated service delivery, and the java-based prototype developed to implement it.
A java-Internet computing environment (JICE) with mulithreading and remote method invocation (RMI) mechanisms is designed as a computing platform to utilize a large collection of computing resources on the Internet fo...
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A java-Internet computing environment (JICE) with mulithreading and remote method invocation (RMI) mechanisms is designed as a computing platform to utilize a large collection of computing resources on the Internet for a distributed parallel computing. This research is intended to exploit the networked idle resources, to develop an infrastructure of global computing platform for applications in the heterogeneous Internet environment, and to evaluate its standard environment to support parallel and distributed computing efficiently. In general, the performance of communications on parallel applications causes a significant impact on the overall performance under the network-based environment. A method of system configuration is proposed to decrease communication time, which is a major bottleneck of performance enhancement. System configuration method (SCM) is a technique to divide a set of distributed nodes into several working groups based on the optimal communication time. Performance of the SCM is evaluated through analysis of communication time under JICE, and verified through the simulation. According to the analysis, the effective number of groups can be determined according to the ratio of shared memory write references. The SCM can enhance the performance of JICE by about two to three times in those applications with a reasonably high ratio of shared-memory references.
The paper presents the advantages of using javaScript functions in interaction with scriptable applets. The concept was tested on JxyZET simulation applet which was developed as a platform independent complement to xy...
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The paper presents the advantages of using javaScript functions in interaction with scriptable applets. The concept was tested on JxyZET simulation applet which was developed as a platform independent complement to xyZET. The later is an authoring tool for the development and visualization of various phenomena in physics. It runs under Motif environment and permits the simulation of flexible bodies built from particles interconnected with springs. In the first part of the paper a short history of JxyZET is given. The original JxyZET was expanded with some scriptable functions. This permits the definition of more complex elastic bodies built from several hundreds or even thousands of particles and springs. These bodies can be easily modified just by changing some parameters within the javascript code included in the parent hypertext. The simulation of complex dynamic systems is investigated. One such system is given by a ball bouncing on an elastic canvas. The introduction of libraries of reusable javaScript function was proposed. The usage of javascript permits the interaction of an user defined algorithm with the simulation tool, in our case JxyZET. The concept of dynamically conditioned simulation runs is explained and the possibilities of dynamically restructured simulation models are demonstrated. This means that during the simulation runs not only the parameters but also the structure of the simulation model can be modified, depending on programmable preconditions written in javaScript. The explained concepts of flexible scriptable functions can be implemented by other similar simulation applets too. In such a way the known nuclear fission reaction was simulated. In the presented example practically all the simulation algorithm was written in javascript. The presented approach permits very flexible simulations of large dynamic systems. The major limiting factor is presented by the capabilities of currently available computer technology, in particular their spee
We describe a java toolkit that is designed to support the creation of powerful and extensible GUI interfaces during the first year computer science course. The goals of this toolkit are to provide: an infrastructure ...
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We describe a java toolkit that is designed to support the creation of powerful and extensible GUI interfaces during the first year computer science course. The goals of this toolkit are to provide: an infrastructure for creating well designed programs that illustrates the concepts of computer science and its practical applications an environment for learning the basic ideas of interface design and for experimenting with a variety of designs a paradigm for building interfaces in java that scales from individual data items to large structures, using recursively displayable container classes. Additionally, the toolkit classes themselves can be studied as examples of proper object oriented design, and of building event listeners.
A problem solving environment (PSE) is a complete, integrated computing environment for composing, compiling and running applications in a specific problem area or domain. A visual programming composition environment ...
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A problem solving environment (PSE) is a complete, integrated computing environment for composing, compiling and running applications in a specific problem area or domain. A visual programming composition environment (VPCE) is described, which serves as a user interface for a PSE, and uses java and CORBA to provide a framework of tools to enable the construction of scientific applications from components. The VPCE consists of a component repository, from which the user can select off-the-shelf or in-house components, a graphical composition area on which components can be combined, various tools that facilitate the configuration of components, the integration of legacy codes into components and the design and building of new components. The VPCE produces output using dataflow techniques in the form of a task graph, annotated with a performance model plus constraints for each component, expressed in XML. In addition, the VPCE supports a domain specific expert system based on JESS (Ernest Friedman-Hill, JESS: The java Expert System Shell. See web site at: http://***/jess/, 1999) to guide the user in component selection and to perform integrity checking.
Self-calibration is a new technique for the study of internal product metrics, sometime called `observations' and calibrating these against their frequency, or probability of occurring in common programming practi...
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Self-calibration is a new technique for the study of internal product metrics, sometime called `observations' and calibrating these against their frequency, or probability of occurring in common programming practice (CPP). Data gathering and analysis of the distribution of observations is an important prerequisite for predicting external qualities, and in particular software complexity. The main virtue of our technique is that it eliminates the use of absolute values in decision-making, and allows gauging local values in comparison with a scale computed from a standard and global database. Method profiles are introduced as a visual means to compare individual projects or categories of methods against the CPP. Although the techniques are general and could in principle be applied to traditional programminglanguages, the focus of this paper is on object-oriented languages using java. The techniques are employed in a suite of 17 metrics in a body of circa thirty thousand java methods.
In the past four years, the java programming language and platform have attracted a lot of attention, largely because of java's cross-platform promise `write once, use anywhere'. Sun Microsystems' slogan, ...
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In the past four years, the java programming language and platform have attracted a lot of attention, largely because of java's cross-platform promise `write once, use anywhere'. Sun Microsystems' slogan, of course, refers to the fact that an application written once to the java platform can be compiled, distributed to any computer or device running java, and execute without modification. This feature looks at the potential of java in the embedded real time environment.
In java, method resolution is done at runtime, by late-binding, with respect to the dynamic type of the target object. Some object-oriented languages such as CLOS propose, in addition, late-binding according to dynami...
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In java, method resolution is done at runtime, by late-binding, with respect to the dynamic type of the target object. Some object-oriented languages such as CLOS propose, in addition, late-binding according to dynamic types of arguments. This feature is known as multi-polymorphism and usually achieved by multi-methods. In this paper, we propose a pure java framework that provides multi-methods, without extending the base javalanguage nor modifying its semantics but intensively using the reflection mechanism of the language. This paper focuses on the algorithms and the data structures involved in the method resolution strategy we have implemented in an optional package called java Multi-Method Framework.
The real-time specification for java (RTSJ) provides a platform that will let programmers correctly reason about the temporal behavior of executing software. Relative to the javalanguage and java virtual machine spec...
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The real-time specification for java (RTSJ) provides a platform that will let programmers correctly reason about the temporal behavior of executing software. Relative to the javalanguage and java virtual machine specifications, the RTSJ strengthens the semantics of the scheduling, memory management, and synchronization algorithms. All the remaining areas except physical memory access help some classes of real-time systems and will produce systems that are relatively accessible to temporal reasoning. As a convenience, the RTSJ includes physical memory access features because many real-time systems require programmatic access to physical memory.
Microcontrollers have been playing an important role in the embedded market. However, the designer of microcontroller based systems must deal with different languages and tools in the hardware and software development...
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ISBN:
(纸本)0769505376
Microcontrollers have been playing an important role in the embedded market. However, the designer of microcontroller based systems must deal with different languages and tools in the hardware and software development, despite of their distinct design process. This paper presents a new design strategy to implement embedded applications described uniquely in java, while maintaining software compatibility throughout the design process. Moreover, the target hardware is a single chip FPGA, taking benefit from their low cost and easy reconfiguration to customize the microcontroller. This papers presents the environment and some results of system synthesis.
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