Enterprise JavaBeans Research Articles

Using J2EE on a large, Web-based project

Working on a large, Web-based, Java 2 Enterprise Edition custom development and enterprise integration project taught the authors many valuable lessons. They present a summary of their experiences, hoping that it might help others working on similar projects to improve their own solutions. The project they describe is a Web-based enterprise software system for a Fortune 100 client, developed using J2EE technologies including Enterprise JavaBeans (EJBs) and JavaServer Pages (JSPs).

ODE: a tool for distributing object-oriented applications

Object-oriented applications are increasingly being deployed in distributed computing environments. Technologies, such as Java RMI, and architectures, such as CORBA, DCOM, and Enterprise Java Beans, are facilitating and enhancing this trend. The performance and eventual success of these applications is dependent on distribution decisions made by the application designer. This decision is a complex one, involving a large number of alternatives and multiple conflicting criteria. Rigorous approaches for effective distribution of object-oriented applications are still lacking. This paper describes the implementation of a practical and effective approach for distributing object-oriented applications. A prototype decision support system—object distribution environment (ODE)—that implements the approach in the form of a user-friendly tool for the design of distributed object-oriented applications is described. ODE has been successfully used in the distribution of a real world distributed object-oriented system.

Component technologies

This one-day tutorial is aimed at software engineering practitioners and researchers, who are familiar with object-oriented analysis, design and programming and want to obtain an overview of the technologies that are enabling component-based development. We introduce the idea of component-based development by defining the concept and providing its economic rationale. We describe how object-oriented programming evolved into local component models, such as Java Beans and distributed object technologies, such as the Common Object Request Broker Architecture (CORBA), Java Remote Method Invocation (RMI) and the Component Object Model (COM). We then address how these technologies matured into distributed component models, in particular Enterprise Java Beans (EJB) and the CORBA Component Model (CCM). We give an assessment of the maturity of each of these technologies and sketch how they are used to build distributed architectures.

Enterprise application integration

Organizations that are able to integrate their applications and data sources have a distinct competitive advantage: strategic utilization of company data and technology for greater efficiency and profit. But IT managers attempting integration face daunting challenges--disparate legacy systems; a hodgepodge of hardware, operating systems, and networking technology; proprietary packaged applications; and more.Enterprise Application Integration (EAI) offers a solution to this increasingly urgent business need. It encompasses technologies that enable business processes and data to speak to one another across applications, integrating many individual systems into a seamless whole.Enterprise Application Integrationprovides a comprehensive examination of EAI. You will find an overview of EAI goals and approaches, a review of the technologies that support it, and a roadmap to implementing an EAI solution. You will also find an in-depth explanation of the four major types of EAI: data-level, application interface-level, method-level, and user interface-level. The book describes in detail the middleware models and technologies that support these different approaches, including: Application servers, including the use of Enterprise JavaBeans (EJB) and ActiveX Message-oriented middleware (MOM) and remote procedure calls (RPCs) Distributed objects, looking at CORBA and COM Database-oriented middleware and standards, including ODBC, JDBC, and OLE DB Java middleware standards Message brokers New process automation and workflow technologyThis practical guide to implementing an EAI solution leads you through all the major steps, including identifying sources of data, building the enterprise metadata model, process integration, identifying application interfaces, mapping information movement, selecting and applying the technologies, testing, and maintenance. Other key topics include integrating packaged applications such as SAP R/3 and PeopleSoft, integrating the supply chain using EAI, the role of XML, and process automation. Comprehensive, practical, and clearly written, this essential resource will help anyone involved in this important business area understand the nature of EAI, its tools and techniques, and how to apply it for a significant business advantage. 0201615835B04062001

An architecture for extensible middleware platforms

AbstractThis article presents a middleware platform architecture whose goals, motivated by the needs of a real‐world application, are the following: separation of functional and non‐functional code in applications, composition of non‐functional properties, and modularity and extensibility of the middleware platform itself. This architecture is inspired by the Enterprise Java Beans platform, and uses a new object composition model to separate and compose the non‐functional properties. In order to evaluate this architecture, we have implemented the JavaPod platform which we have used to implement a prototype of the application that motivated our goals. The results of these experiments show that our goals can indeed be achieved with our architecture. Copyright © 2001 John Wiley & Sons, Ltd.

Multi-technology distributed objects and their integration

Research on software objects, components, middleware, and component-based applications concerns among others ActiveX controls, JavaBeans (JBs), the Microsoft Transaction Server (MTS), Enterprise JavaBeans (EJBs), and how they can interoperate with each other. Is their interoperation possible? Which elements are responsible for the software objects' incompatibility? Is compatibility a responsibility of the objects or of their underlying architectures? In this article, we discuss object compatibility problems by outlining three basic middleware remoting technologies: the OMG's Common Object Request Broker Architecture (CORBA), Microsoft's Distributed Component Object Model (DCOM), and Sun's Java Remote Method Invocation (RMI), discussing the basic incompatibility points, and overviewing the basic strategies for bridging the gap between CORBA, DCOM, and RMI.

Interval parameters for capturing uncertainties in an EJB performance model

Exact as well as approximate analytical solutions for quantitative performance models of computer systems are usually obtained by performing a series of arithmetical operations on the input parameters of the model. However, especially during early phases of system design and implementation, not all the parameter values are usually known exactly. In related research contributions, intervals have been proposed as a means to capture parameter uncertainties. Furthermore, methods to adapt existing solution algorithms to parameter intervals have been discussed. In this paper we present the adaptation of an existing performance model to parameter intervals. The approximate solution of a queueing network modelling an Enterprise JavaBeans server implementation is adapted to interval arithmetic in order to represent the uncertainty in some of the parameters of the model. A new interval splitting method is applied to obtain reasonable tight performance measure intervals. Monotonicity properties of intermediate computation results are exploited to achieve a more efficient interval solution. In addition, parts of the original solution algorithm are modified to increase the efficiency of the corresponding interval arithmetical solution.

Component based distributed systems – CORBA and EJB in context

Astronomy, like other sciences, is highly collaborative, so it is no surprise that astronomical computing environments have become increasingly distributed in nature. Therefore the interest in benefiting from new developments in distributed computing technologies is clear, but to reap these potential benefits we must overcome the problems posed by the heterogeneous mix of different architectures and operating systems that occur. This mix has made information flow between systems at best difficult and organizations have not been able to fully harness one of their most valuable assets, namely information. This paper introduces the Common Object Request Broker Architecture ( CORBA) and Enterprise Java Beans ( EJBs), and puts forward a rationale as to why they have the potential to provide the required integration platform. These component based distributed technologies, allow disparate, heterogeneous legacy data systems to be integrated with current systems and they also support the incremental growth of current systems to meet evolving requirements.

Distributed component software security issues on deploying a secure electronic marketplace

A secure electronic marketplace involves a significant number of real‐time transactions between remote systems, either for commercial or for authentication purposes. The underlying infrastructure of choice to support these transactions seems to be a distributed component architecture. Distributed component software (DCS) is the natural convergence of client/server network computing and object oriented technology in a mix providing reusability, scaleability and maintainability for software constructs. In DCS a client acquires references to objects provided by components located to remote machines and invokes methods of them as if they were located in its native environment. One implementation also provides the ability to pass objects by value, an approach recently examined also by others. The three major models in the distributed component software industry are OMG’s CORBA, Sun’s Enterprise Java Beans, and Microsoft’s DCOM. Besides these, we will discuss the progress for interoperable DCS systems performed in TINA, an open architecture for telecommunications services based on CORBA distributed components. In this paper the security models of each architecture are described and their efficiency and flexibility are evaluated in a comparative manner. Finally, upcoming extensions are discussed.

Legacy integration-changing perspectives [Cobol

Dusty Cobol card decks, difficult-to-maintain programs, and software generally incompatible with current state-of-the-art application frameworks: that's legacy. Or is it? Start with the cleansing effect of Y2K, add the Internet and e-commerce, and throw in component technologies such as Corba, COM, and Enterprise JavaBeans, the standardization effort behind XML, and the resurgent interest in data, and you'll find new meaning and vitality for the term legacy. Estimated at over 100 billion lines of code, most of it Cobol, it drives the world's infrastructure. The end result is a new appreciation of legacy and a search for ways to capitalize on its potential. Cobol programs and data are being viewed in a new positive light with options for interconnection and integration for both code and data.

Component-based development: from buzz to spark

Component-based development (CBD) is the building of software systems out of prepackaged generic elements. The current excitement about CBD results from the convergence of four phenomena originating from quite different backgrounds: on the scientific side, the progress of modern software engineering ideas with their special emphasis on reuse. On the industrial side, the widespread success of theoretically unpretentious but practically useful techniques for building GUIs, databases, and other parts of applications out of components. On the political side, the push by some of the major players for competing interconnection technologies: CORBA, COM, and Enterprise JavaBeans. In the software world at large, the generalization of object technology, which provides both the conceptual basis and the practical tools for building and using components. The catalyst behind component-based development is the growing realization by the software industry that something must be done to control the costs of developing software products and boosting their quality.

Support for Enterprise JavaBeans in Component Broker

Objects were introduced as programming constructs that encapsulate data and methods. The goal was to foster software reuse and simplify the developer's concept of how a task was implemented. The developer need only know the interfaces to an object to use its functionality. Distributed objects simplified conceptualization further by removing the need to know the locality of an object. Clients invoked methods on distributed objects as if the objects existed in the client's process. Beyond this location transparency, the need arose for distributed objects to survive beyond the life of one client, to be able to support thousands or millions of clients, and to participate in transactions. To support scalability, persistence, and transactional semantics with no dependencies on platform or data store, models were developed. In this paper we look at various component models, focusing on two: IBM's Component Broker and Sun's Enterprise JavaBeansTM. We show that they augment each other and propose how Enterprise JavaBeans can use the additional functions of Component Broker to provide a scalable, transactional, and persistent environment to clients of both worlds.

Implementing Java computing: Sun on architecture and applications deployment

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.