Enterprise computing: the Java factor

The ubiquitous availability of Web browsers on multiple platforms and user familiarity with browser technology provide numerous advantages: a uniform interface; support for multimedia and user interaction and collaboration; a simple communication protocol that has been implemented in all major hardware and software platforms; and support by almost all vendors who package Web engines within their products. Such factors have expedited the implementation of network centric computing as a productive infrastructure for corporate environments. The addition of Java, with its ability to build cross platform application logic into a browser, gives network centric computing the potential to better meet enterprise computing needs. Because it lets users interact with the application on the client rather than the server, Java enables better utilization of both the server and the client's computational capability. Java can also provide sessions state information (for client side session control and resource management) in an otherwise stateless Web world. Besides naturally decentralizing application execution, Java makes it possible to decentralize application deployment. In large enterprises, organization wide applications such as personnel timekeeping or document routing can benefit from Java implementations. One immediate impact is a noticeable reduction of the server load during peak hours. Finally, Java enabled browsers can provide greater functionality than HTML     

Implementing Java computing: Sun on architecture and applicationsdeployment

SunIR is the information technology organization within Sun Microsystems that is responsible for developing and maintaining the IT environment that supports all of Sun's business operations worldwide. This environment supports more than 20,000 employees in 180 locations in 55 countries. It currently consists of a global network with more than 3,000 subnets, 35,000 desktops, 9,000 servers and 200 internally developed distributed business applications, which are accessed by employees as well as customers, vendors and other business partners outside Sun's corporate intranet. In the process of providing the infrastructure and computer systems upon which all of Sun's business is run, SunIR also serves as a proving ground for many Sun products. We expect this architecture to continue to evolve as we learn more and as new technologies become available. We are currently working to incorporate Enterprise JavaBeans technology into this model, as we continue to build and deploy enterprise applications that support the operations of a $9 billion company     

Distributed computing for multidisciplinary design optimization using Java

The programming language Java (recently referred to as the computer language of the Web) offers substantial possibilities for the type of complex engineering problems typically encountered in multidisciplinary design optimization (MDO) problems. In order to demonstrate the potential uses of Java for MDO problems, this paper presents the development of the Web Interface for complex engineering design (WICkED) software, which simulates the convergence of a decomposed complex system in a distributed computing environment and computes the sensitivity derivatives of the system with respect to the independent input variables using the GSE method or the finite difference method. In this application, one computer is designated as the server and sends out required inputs to a number of client subsystems over the Internet. A number of client computers can connect to the server and then receive the inputs necessary to calculate the solution to their model. As the code necessary to solve the model already exists at the client, only the inputs have to be sent over the network. When the client has solved the calculation, it returns the results to the server which processes the result to produce new inputs.WICkED is written entirely in the Java programming language which allows server and clients to exist on completely different computer types and in heterogeneous, distributed networks. A number of parametric studies on the behaviour of complex systems in a distributed environment are performed and the results are reported in this paper. This research serves to identify potential problems as well as advantages in using Java for MDO applications.     

A Java framework for massively distributed symbolic computing

We present a framework for implementing massively distributed applications in symbolic computing. Using this framework, computations with massive resource requirements can be distributed and processed in parallel on a network of workstations or on a large scale network such as the Internet. For each concrete application only minimal code is needed to complement the generic framework in order to enable large scale distributed processing of the application.Our framework introduces a “divide and be conquered” model for massively distributed computations. We compare this model to a more traditional one, in a symbolic computing setting. We stress the major problems and propose solutions for some of them.     

Java enabling collaborative education,health care,and computing

Web technologies – in particular linked Java servers and clients – allow new dynamic collaborative environments linking people and computers. We describe the architecture of a system, TANGOsim, that combines a Java collaborative environment with an executive providing general message filters, and an event-driven simulator. The initial application is to command and control, but we describe how this approach can also be used in other areas, such as health care, scientific visualization and (distance) education. © 1997 John Wiley & Sons, Ltd.     

Java card: Internet computing on a smart card

The smart card-which offers Internet programmers a truly safe place to generate and store a private encryption key-will soon be recognized as a useful component of Internet computing. Until now the security precautions surrounding smart-card technology have effectively prevented its use in general computing systems, but the recent implementation of the secure Internet language Java on a smart card not only opens up smart-card programming to everyone but connects smart cards directly with standard programming applications in use on the Internet     

Bayanihan: building and studying web-based volunteer computing systems using Java

Project Bayanihan is developing the idea of volunteer computing, which seeks to enable people to form very large parallel computing networks very quickly by using ubiquitous and easy-to-use technologies such as web browsers and Java. By utilizing Java’s object-oriented features, we have built a flexible software framework that makes it easy for programmers to write different volunteer computing applications, while allowing researchers to study and develop the underlying mechanisms behind them. In this paper, we show how we have used this framework to write master-worker style applications, and to develop approaches to the problems of programming interface, adaptive parallelism, fault-tolerance, computational security, scalability, and user interface design.     

Searching for nonlinear feedback shift registers with parallel computing

Nonlinear feedback shift registers (NLFSRs) are used to construct pseudorandom generators for stream ciphers. Their theory is not so complete as that of linear feedback shift registers (LFSRs). In general, it is not known how to construct all NLFSRs with maximum period. The direct method is to search for such registers with suitable properties. Advanced technology of parallel computing has been applied both in software and hardware to search for maximum period NLFSRs having a fairly simple algebraic normal form.     

On the design of global object space for efficient multi-threading Java computing on clusters

The popularity of Java and recent advances in compilation and execution technology for Java are making the language one of the preferred ones in the field of high-performance scientific and engineering computing. A distributed Java Virtual Machine supports transparent parallel execution of multi-threaded Java programs on a cluster of computers. It provides an alternative platform for high-performance scientific computations. In this paper, we present the design of a global object space for a distributed JVM. It virtualizes a single Java object heap across machine boundaries to facilitate transparent object accesses. We leverage runtime object connectivity information to detect distributed shared objects (DSOs) that are reachable from threads at different nodes to facilitate efficient memory management in the distributed JVM. Based on the concept of DSO, we propose a framework to characterize object access patterns, along three orthogonal dimensions. With this framework, we are able to effectively calibrate the runtime memory access patterns and dynamically apply optimized cache coherence protocols to minimize consistency maintenance overhead. The optimization devices include an object home migration method that optimizes the single-writer access pattern, synchronized method migration that allows the execution of a synchronized method to take place remotely at the home node of its locked object, and connectivity-based object pushing that uses object connectivity information to optimize the producer–consumer access pattern. Several benchmark applications in scientific computing have been tested on our distributed JVM. We report the performance results and give an in-depth analysis of the effects of the proposed adaptive solutions.     

Device level communication libraries for high‐performance computing in Java

Since its release, the Java programming language has attracted considerable attention from the high‐performance computing (HPC) community because of its portability, high programming productivity, and built‐in multithreading and networking support. As a consequence, several initiatives have been taken to develop a high‐performance Java message‐passing library to program distributed memory architectures, such as clusters. The performance of Java message‐passing applications relies heavily on the communications performance. Thus, the design and implementation of low‐level communication devices that support message‐passing libraries is an important research issue in Java for HPC. MPJ Express is our Java message‐passing implementation for developing high‐performance parallel Java applications. Its public release currently contains three communication devices: the first one is built using the Java New Input/Output (NIO) package for the TCP/IP; the second one is specifically designed for the Myrinet Express library on Myrinet; and the third one supports thread‐based shared memory communications. Although these devices have been successfully deployed in many production environments, previous performance evaluations of MPJ Express suggest that the buffering layer, tightly coupled with these devices, incurs a certain degree of copying overhead, which represents one of the main performance penalties. This paper presents a more efficient Java message‐passing communications device, based on Java Input/Output sockets, that avoids this buffering overhead. Moreover, this device implements several strategies, both in the communication protocol and in the HPC hardware support, which optimizes Java message‐passing communications. In order to evaluate its benefits, this paper analyzes the performance of this device comparatively with other Java and native message‐passing libraries on various high‐speed networks, such as Gigabit Ethernet, Scalable Coherent Interface, Myrinet, and InfiniBand, as well as on a shared memory multicore scenario. The reported communication overhead reduction encourages the upcoming incorporation of this device in MPJ Express ( http://mpj‐express.org ). Copyright © 2011 John Wiley & Sons, Ltd.     

A grid middleware for distributed Java computing with MPI binding and process migration supports

“Grid” computing has emerged as an important new research field. With years of efforts, grid researchers have successfully developed grid technologies including security solutions,resource management protocols, information query protocols, and data management services. How-ever, as the ultimate goal of grid computing is to design an infrastructure which supports dynarnic,cross-organizational resource sharing, there is a need of solutions for efficient and transparent task re-scheduling in the grid. In this research, a new grid middleware is proposed, called G-JavaMPI. This middleware adds the parallel computing capability of Java to the grid with the support of a Grid-enabled message passing interface (MPI) for inter-process communication between Java processes executed at dif-ferent grid points. A special feature of the proposed G-JavaMPI is the support of Java process migration with post-migration message redirection. With these supports, it is possible to migrate executing Java process from site to site for continuous computation, if some site is scheduled to be turned down for system reconfiguration. Moreover, the proposed G-JavaMPI middleware is very portable since it requires no modification of underlying OS, Java virtual machine, and MPI package. Preliminary performance tests have been conducted. The proposed mechanisms have shown good migration efficiency in a simulated grid environment.     

Java for parallel computing and as a general language for scientific and engineering simulation and modeling

We discuss the role of Java and Web technologies for general simulation. We classify the classes of concurrency typical in problems and analyse separately the role of Java in user interfaces, coarse grain software integration and detailed computational kernels. We conclude that Java could become a major language for computational science, as it potentially offers good performance, excellent user interfaces and the advantages of object-oriented structure. © 1997 John Wiley & Sons, Ltd.     

A formula for computing the number of quadtree node fragments created by a shift

A formula is provided to compute the number of new blocks resulting from the decomposition induced by a shift of a single quadtree node of arbitrary size by an arbitrary amount. A precise calculation is also presented for the average number of Black nodes required to represent a square of width 2^m in a region quadtree.     

Bringing Java to the enterprise: Oracle on its Java server strategy

Java is becoming the predominant language for defining and deploying complex business logic across all tiers of the enterprise. Java is uniquely suited to distributed information systems, and clearly critical to the success of Oracle's network computing initiative. No other language combines the features required in these environments. This paper surveys five aspects of our Java product strategy. Unless otherwise stated, these components are included in the Oracle 8.1 software development kit, SDK2, which is under test at a small number of sites. Over the past 20 years, SQL has become the “shape” of the world's store of data. In many ways, Java represents a practical, ubiquitous means for augmenting this structure with the arbitrarily complex operational semantics that only a general-purpose, object-oriented programming language can provide. Such logic is inherently distributed, and may be freely deployed on any network computing tier. The combination of ubiquitous SQL data and Java behavior will generalize relational database management systems into the information servers that are so critical to the future of network computing     

Java for high‐performance network‐based computing: a survey

There has been an increasing research interest in extending the use of Java towards high‐performance demanding applications such as scalable Web servers, distributed multimedia applications, and large‐scale scientific applications. However, extending Java to a multicomputer environment and improving the low performance of current Java implementations pose great challenges to both the systems developer and application designer. In this survey, we describe and classify 14 relevant proposals and environments that tackle Java's performance bottlenecks in order to make the language an effective option for high‐performance network‐based computing. We further survey significant performance issues while exposing the potential benefits and limitations of current solutions in such a way that a framework for future research efforts can be established. Most of the proposed solutions can be classified according to some combination of three basic parameters: the model adopted for inter‐process communication, language extensions, and the implementation strategy. In addition, where appropriate to each individual proposal, we examine other relevant issues, such as interoperability, portability, and garbage collection. Copyright © 2002 John Wiley & Sons, Ltd.     

Scientific computing with Java and C++: a case study using functional magnetic resonance neuroimages

Modern systems for the analysis of image‐based biomedical data, such as functional magnetic resonance imaging (fMRI), require fast computational techniques and rapid, robust development. Object‐oriented programming languages such as Java and C++ provide the foundations for the development of complex data analysis applications. This case study explores the advantages and disadvantages of using these two programming environments for scientific computation as typified in the analysis of fMRI datasets. C++ is well suited for computational and memory optimization while Java is more compliant to the object‐oriented paradigm, supports cross‐platform development and has a rich set of application programming interface (API) classes. The same data model and algorithms were implemented in C++ and Java, and a user interface was developed with the Java API. Comparisons were made with respect to computational performance and ease of development. Benchmarks show that C++ generally outperforms Java, while Java is easier to use, leading to more robust code and shorter development times. However, with the advent of newer just‐in‐time compilers, Java performance is at times comparable to C++. The latest Java virtual machine technology is closing the gap and eventually Java should be a good compromise between efficient algorithm performance and effective application development. Copyright © 2004 John Wiley & Sons, Ltd.     

Java语言与Java技术

介绍Ｊａｖａ语言对业界的影响，Ｊａｖａ平台及当前正在发展着的Ｊａｖａ技术。     

Java编译程序技术与Java性能

概述了Java编译程序技术,把Java编译程序分成5类:具有解释技术的编译程序;具有及时(JIT)编译技术的编译程序;具有自适应优化技术的编译程序;本地编译程序和翻译程序.详细描述和分析了它们的体系结构和工作原理.同时也分析了编译程序技术对Java性能的影响.     

Java and activeX: Background and risks to the business

Java and Active X, commonly known as mobile code, are becoming more prevalent as the Internet and more specifically the World Wide Web develops. Concerns are being voiced about the security of these utilities and what impact they may have on the security of systems making use of Internet-based services. This article describes the background to and usage of these utilities, the likely threats and what precautions can be taken to minimize any risk.