The ADP Display, shown below, demonstrates the integration of a Java front end with a real-time C/C++ backend. The back end runs on VxWorks¨ using our publish/subscribe Message Oriented Middleware, while the Java front end communicates with the real-time backend using the same publish/subscribe paradigm on Ethernet. The network middleware implementation supports multicast thereby enabling multiple displays without wasting valuable bandwidth. All message creation/access on the display side is via Java classes that have been automatically generated from the C++ backend header files by Dot21's C2J tool.

C2J is a powerful tool that can automatically parse your C/C++ message definition files to create corresponding Java class files that contain accessor methods for all data members, including bit fields. Even though Java does not support bit fields, the Java classes generated by C2J can access these fields easily and automatically by masking and shifting. Application programmers are completely shielded from this low-level complexity, and there's no IDL to worry about!

The display software is based in part on OpenMap™, an Open-Source JavaBeans-based mapping toolkit. The rack-mountable target hardware runs Linux and can be booted from either disk or flash memory. The system contains no keyboard or mouse Ð all input is through a touchscreen. Virtual on-screen keyboards and keypads allow textual input when necessary. Live data can be extracted and burned to a CD, then played back at a later time or analyzed in more detail using Dot21's fully compatible Data Analysis and Reduction tools.

Because Dot21's Middleware uses a publish/subscribe design pattern, many instances of this display can be active at any time. And because the ADP Display runs on Java, setting up a classroom training environment where each student has his own laptop display is trivial.

VxWorks is a registered trademark of Wind River Systems. OpenMap is a trademark of BBN Technologies