>> I can say that flying in an aircraft controlled by Java is >> probably safer than one controlled by C, until garbage >> collection kicks in just when you need reverse thrust. > >Though I still would not want my life entrusted to Java, it is worth >pointing out that I read a blurb (can't remember the company name) about a >JVM that allegedly "guarantees deterministic performance." I've been lurking on this thread for a while, but I guess I should put in my $.02 .... "Vanilla" Java clearly has a number of problems with respect to determinstic real-time performance: the absence of stack-based objects, the need to account for gc, the incomplete specification of how priorities affect scheduling, the absence of provisions for avoiding priority inversion, the absence of an absolute "sleep", the relatively limited set of facilities for asynchronous event handling, and several others. Nevertheless the language's very high degree of portability and safety (more than Ada's in fact) have sparked interest from the real-time community. There was a requirements-gathering effort last year led by NIST, involving major stakeholders from both the real-time and Java communities. Since early in 1999 two efforts have been underway at addressing Java's shortcomings in the real-time arena: one under the auspices of Sun's Java Community Process, and the other one (produced by the "J-Consortium") independent of Sun. There are no good technical reasons why there should be two such efforts, but various companies' business interests have led them into one camp or the other, or into both. Both groups released their specs at the Embedded Systems Conference in San Jose last month. If you want more information, check their web sites: http://www.rtj.org (the Real-Time for Java Experts Group under Sun's JCP) or http://www.j-consortium.org (for the J-Consortium's spec). Ben Brosgol [log in to unmask]