IBM Corp wheeled out its promised implementation of the Java Virtual Machine for its System 390 mainframe line at London’s Java Expo Show this week, demonstrating a Java applet it had pulled straight from the Internet. Java for OS/390, said IBM software strategy consultant Mark Cathcart, fits well with the Internet Server for OS/390, part of the Internet bundle for MVS promised back in February (CI No 2,850) and now available. It means that Internet-enabled applications, CGI Common Gateway Interface programs, and extensions of and access to existing applications and databases, can all be run or be integrated with the mainframe. Large customers interested in hosting IBM’s new Network Computers with a mainframe, or writing thin-client applications, might also be interested. On the System/390, the Java Virtual Machine is part of OS/390 OpenEdition, which has recently been certified X/Open 95-compliant: at least MVS/ESA 5.2.2 is required. It was converted from the AIX version, along with all the standard classes. Java’s AWT windowing tool-kit is implemented in X Windows. Because OS/390 works with packed decimal, IBM had to rework the IEEE floating point portions of the Java Virtual Machine, and also had to convert ASCII to EBSIDIC extended binary code character sets. A beta test program is beginning now, with a free beta version available for download (from http://ncc.hursley.ibm.com/javainfo) by the end of the week. Next year, the Java Virtual Machine will be integrated in to the OS/390 operating system. In the future – and that’s the not too distant future, says IBM – it will add access to CICS transaction processing systems and DB2 and IMS databases via Java classes yet to be written, and an implementation of Sun Mi crosystems Inc’s Java DataBase Connectivity database communications specification for the mainframe. All could emerge before the year is out. As for Java on other proprietary IBM systems, OS/400 remains a committed plan, while a VM/ESA version is a somewhat more distant future plan.
