1. JCA 2.0 Eric. Boucher – APS boucher@aps.anl.gov EPICS Collaboration Meeting - June 18-20, 2003

2. Introduction What is JCA Why a new version New features Compatibility Future of JCA

3. What is JCA JCA is a java implementation of the Channel Access library It allows standalone Java application to connect to CA servers. It is also possible, with some restrictions to develop web-based applications. It is not a pure Java implementation.

4. Why a new version Previous version was released in 1999 More and more users Release of CA 3.14 Cleaner API Add new features

5. Overview New design Backward compatible with JCA 1.0 Support for both EPICS 3.13 and 3.14 Requirement: Java 1.2 or higher Epics 3.13 or higher Successfully build for the following platforms: Win32 Linux-x86 Solaris-sparc

6. New Features Separation between interfaces and implementation Introduction of the concept of Context All exception handlers now implemented Many helper functions added Different level of programation

7. Design Context Channel Java application

8. Thread Control CA INTERNAL Application Context Thread EXTERNAL Application Context Thread CA Thread

9. Browser Integration Load applet code WEB server CA server JCA 2.0 Browser Java Plugin

10. JCA 1.0 JCA1.0 Application Bridge JCA2.0 Backward compatible Possible loss of performance

11. EPICS 3.13 Preemptive callback disabled Only one context allowed

12. Future of JCA Support from different labs. – SNS ORNL – COSYLab – DESY Web page Mailing list Pure java version JCA components