In a week that now seems to have raced by in a blur, the main hall at the
What followed was a series of product or concept demonstrations and chats with the engineers or founders of the products, typically highlighting the fact that Java was at the heart of their pretty cool products. The diversity of the products on display was what stood out for me and served to highlight the ubiquity of the Java language and platform, as mentioned back on day one by Rich Green. In the interest of keeping some creative juices in reserve for writing up all the other stuff I learned this week, I will just highlight some of the projects here and include links you can easily find out more.
Java Visual VM
This tool looks like it could be pretty useful for when you need to get in to debugging some of the more extreme bugs that pop up or want to get some numbers that show how your application performs. It should also serve a great educational purpose for showing people in an easy-to-understand way what is going on inside the VM when it’s running code.
The tool makes use of tools and applications such as jp, jinfo, jstack and jmap and displays a lot data through several views, amongst others; the system properties, start-up arguments, thread dump, heap dump, garbage collection and more. It can be hooked up to a running Glassfish v3 instance and show information related to JSP’s, servlets and socket data.
The best feature should be the fact that it barely impacts performance when running and can be set to monitor remote JVMs (backwards compatible to Java 1.2) the tools can also save data as snapshots to file for offline analysis at a later time. Release Candidate 1.0 was just released in time for JavaOne and you can read more about the project here: https://visualvm.dev.java.net/
Java Games and Project Darkstar
The technical sessions about Darkstar, Sun’s project to build a gaming platform, were all over-subscribed this week and Chris Melissinos (who has the best job title going) – Chief Gaming Officer for Sun – was brought on stage to demonstrate their progress. He explained that Darkstar is a highly fault tolerant games server, think Java EE for games, he said. The team have just released what was termed a ‘multimode’ implementation which means easy clustering and scalability and you can learn more at http://www.projectdarkstar.com. The demo we saw was a game named Call of the Kings (http://www.callofthekings.com) and was being served from a Darkstar server in the
When setting up the
Some of the numbers yielded interesting facts though, such as the sensors attached to escalators outside the main hall. One the escalators at the end of a general session was reversed to provide two upward moving stairways for attendees leaving the area – the data showed that the escalator wasn’t allowed to come to a stop before being reversed so there was a huge power spike because the motors began turning in reverse while the stairs were still moving the other way. These are ofcourse trivial uses of the ‘motes’ which are called pervasive computers, but we were told of real-world applications that include a deployment in the Napa Valley on vineyards where temperature and soil moisture are measured to more accurately control when an area should be watered. Logistics management at major ports also seems to be another key use, with the motes being installed in containers and box-cars, enabling the management of the port or have much cleared picture of what is where across their site.
What does this have to do with Java, though? Well, the tiny computers in the ‘motes’ run Java applications which means that Java developers can now create applications without needing to worry about interfacing with some low-level embedded code – it’s all in Java. The motes are about the size of a small matchbox and have modified USB connectors on the side to which a number of sensors or input devices can be attached, the motes themselves capable of connecting to each other via an RF mesh network. Pretty cool stuff really and you can read more at: http://www.sentilla.com/software.html
The second part of this article will highlight what seemed to be the ‘product of the show’, the Pulse Smartpen from Livescribe as well as: information about Tommy Junior, jMars and how CERN are using Java to help us better understand the universe.