Nearly everyone has heard the term middleware, but relatively few actually have a full understanding of its meaning and significance. In this article, author Cliff Berg reveals the current state of Java middleware. He compares the many categories of products, explains the various features, and discusses how -- and to what degree -- these features actually are supported. The author details new APIs, including Enterprise JavaBeans, the Java Transaction API, and JDBC2, in the context of current and anticipated Java middleware. Finally, he explains the role of application servers and compares them with other kinds of Java middleware.
Most Web-based applications collect data using long HTML-based forms -- a technique most users find confusing and aggravating. If you're an application developer, your users deserve their data collected in a simple and understandable workflow. Likewise, developers need a way to easily maintain and update this workflow. In this article, Michael Ball explains how to use an Extensible Stylesheet Language (XSL)-based application employing the Dispatcher design pattern to create simple workflows and a reusable API. (1,600 words; October 19, 2001)
4. The state of Java middleware, Part 2: Enterprise JavaBeans
By the time Sun released version 1.0 of the Enterprise JavaBeans (EJB) specifications in March of 1998, several vendors not only had endorsed this new server-side component architecture, but also had begun developing products based on the evolving specifications. Today there are several products that fully implement the required features of EJB 1.0, and some that also support optional EJB features. This article provides an overview of EJB and looks at how some of these products support EJB. If you have wondered what EJB is or have bits and pieces of information about it but are missing the big picture, you need to read this article.
This tip introduces you to the EjbProxy utility class. It instantiates and invokes a remote EJB without coupling your code directly to a specific implementation of that particular EJB. (1,400 words; October 12, 2001)
The Java 2 Enterprise Edition (J2EE) Platform is defined by four key pieces: the specification, the reference implementation, the compatibility test suite, and the BluePrints program. BluePrints describes the best practices and design guidelines for a distributed component architecture. This article introduces an eight-step J2EE development methodology based on the Rational Unified Process and the BluePrints sample application. By reading this article, you will better understand many important J2EE architecture topics, and be able to apply that knowledge to extend and modify this simple methodology to solve your special business problems. (3,600 words; September 28, 2001)
You need to juggle many balls when embarking on an enterprise Java project: vendor relationships, chronic over-engineering in both design and development, staying sane. Each carries inherent dangers, some of which are obvious, while others are not. But all of these hazards are avoidable. In this article Humphrey Sheil analyzes the top 10 dangers that threaten the success of all enterprise Java projects and outlines some ways to avoid them. (4,500 words)
If you plan to build a scalable and highly available Website, you need to understand clustering. In this article, Abraham Kang introduces J2EE clustering, shows how to implement clusters, and examines how Bluestone Total-e-server, Sybase Enterprise Application Server, SilverStream Application Server, and WebLogic Application Server differ in their approaches. With this knowledge you will be able to design and implement effective and efficient J2EE applications. (5,900 words)
Because most developers build their Web applications in a nonclustered environment, those applications often break when moved into a cluster. In this article, the second of two, Abraham Kang explains the programming, setup, and management issues related to clustering. With this knowledge, you will be able to write code that is clusterable from its inception, thus avoiding pitfalls later. (2,700 words)
