Michael Havey

Though most Java developers think of the Java Native Interface (JNI) as a framework for developing native libraries that can be called from Java, relatively few know that JNI also supports communication in the reverse direction: it provides native programs written in C with the ability to call Java objects. However, the coding is thorny; logic that can be coded readily in a few lines of Java requires several times more lines of C, thanks to JNI's granular programming model and peculiar approaches to exception handling and garbage collection. This article explores the nature and typical use of the C-to-Java JNI interface and presents the design of a framework that eases the programming effort. The JNI Architecture As Figure 1 illustrates, JNI is actually a pair of APIs: "... (more)

BPM Theory for Laymen

In most software topics, the boundary between theory and practice in software is clearly demarcated: theory is for academics who seldom descend from the ivory tower, practice is for industry professionals who have long forgotten the concepts and application of theory. In concurrency, for example, most developers either know or have programmed semaphores, but few remember the conceptual u... (more)

The Flesh and Bone of SOA

Over the years business processes have become automated to the point that the BPM community now considers the SOA language BPEL, designed for the orchestration of Web Services, as the best platform for building contemporary processes. But many processes retain some level of human activity, and BPEL's support for human interaction is problematic. Most attempts to integrate human workflow ... (more)

State Machines and Workflow

The state machine is one of the most successful ideas in the history of computing. Alan Turing built a model of computability around the concept, and in doing so became the father of computer science. Mealy, Moore, Harel, and other theorists expanded the idea, influencing engineers of digital logic, real-time, and embedded systems whose designs are peppered with state machines and diagra... (more)

Modeling Web Services Choreography with New Eclipse Tool

Choreography is the dark continent of Web services: few onlookers have traveled there, and many question whether there are any riches to be brought home from the trip. In the first place, choreographies bear such a striking resemblance to business processes that the novice might think that the two types of artifacts are indistinguishable. After all, isn't choreography just a way to descri... (more)