That What It Takes
A new diagnostic tool for Java
Writing this blog has been tricky, because the big news of the day is the release of the VisualVM project, a new all-in-one troubleshooting tool for the Java platform. Problem is, while a couple of people have blogged about it, almost nobody has described it in significant detail. And that makes it hard to know what you're going to get with the binary download.
Fortunately, someone mentioned that it had been shown at JavaOne, and while it doesn't appear in any of the technical session PDF's that I looked through, Mandy Chung has posted a PDF (592 KB) of the BoF session, "Visualize Runtime Problems:
A New All-in-One Troubleshooting Tool".
Reading this, we can better understand the runtime problems that VisualVM is meant to address, specifically given the fact that most JDK diagnostic tools are geared to a single task (consider jstack, jmap, jstat, jinfo, jhat, etc.). There's no integration between tools, and no performance tool at all. So, the VisualVM offers "a graphical tool from monitoring, performance
analysis to troubleshooting", suitable for production use, as it can be attached to a running JVM. VisualVM integrates integrates jps, jstack, jstat, jmap, and jinfo, along with CPU and memory profiling functionality, and a heap walker for heap analysis.
And beyond that, I think the next step is to download the VisualVM and try it out. Hmm... 7.8 MB zip. Hope it runs on the Mac Java 5.0 JVM...
Also in Java Today,
OpenMark is an innovative online assessment system developed by The Open University, then released under the GPL. OpenMark differs from many CAA systems in its emphasis on feedback, its allowing of multiple attempts, the breadth of interactions supported, and its design for anywhere, anytime use.
Version 1.4.0 is the first stable release since the code was open-sourced. The developers say, "please give it a try and let us know what you think."
Ericsson AB has submitted JSR-319, Availability Management for Java. "The purpose of the Availability Management for Java is to enable availability frameworks to supervise and to control Java runtime units in a standardized way." To do this, the framework is meant to "coordinate redundant resources within a cluster to deliver a system with no single point of failure," by deciding how to distribute software resources across the cluster, manage activation and deactivation of those resources and monitor their health, handle error recovery, and more. The JSR review period runs through October 29.