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Slip Sliding Away

Posted by editor on September 11, 2007 at 7:26 AM PDT

Event handling getting out of hand?

It would be nice if you could count on a certain consistent level of latency from your users, but of course, that's unrealistic. If you're lucky enough to have a popular application, chances are you'll occasionally see bunches of incoming requests all coming in at the same time. Perhaps it'll be too much for your app to deal with at one time, but can you just block while you work through all the events? Can you use threading to help your app better adapt to the real-world ebb-and-flow of event processing?

In today's Feature Article, Lorenzo Puccetti as a few ideas for working Towards a Timely, Well-Balanced, Event-Driven Architecture:

It is often possible to design receivers in which dealing with one event or 100 events takes roughly the same time or, to be more accurate, in which the code does not scale linearly with the number of events. This is because whether it is one event or 100 events, the same number of calls to the database, the filesystem, or to a CPU-intensive mathematical library might still be required. And it is these operations in which the most time must be spent.

In this article, we discuss a simple framework that forms the basis for a powerful and flexible solution to decouple event production and consumption while supporting a pluggable "event-dispatching" policy.

This article took a long time to develop, with some helpful feedback from Brian Goetz to ensure thread-safety and eliminate unnecessary complications in the concurrent logic. We thank Brian for his feedback on this piece.

The latest Java Mobility Podcast is Java Mobility Podcast 18: Learn new UI techniques with phoneME UI Labs and Java ME . "phoneME UI Labs is the one stop resource for developers to learn about the advanced UI technologies in Java ME platform. Aastha Bhardwaj talks about scalable vector graphics (SVG) in JSR 226 and JSR 287 and the demos that developers can find in UI Labs."

We mentioned Sun Tech Days last week, and in today's Weblogs, Ryan Shoemaker has a look at the Boston event, which starts today. In Sun Tech Days - Boston, MA, he writes, "Sun is kicking off the 2007-2008 Tech Days season in Boston, MA this week on Sept 11 & 12. On the 11th, you can attend NetBeans Day(FREE), OpenSolaris Day(FREE), or University Day(FREE)."

Joshua Marinacci, working on JavaFX tooling, explains the various JavaFX offerings in JavaFX != JavaFX Script. "I recently gave a presentation at the Portland Java Users Group about Java FX. After talking to some of the fine members of PJUG I realize that there is a lot of confusion about JavaFX and JavaFX script."

And in case you were still wondering, Tim Boudreau is still alive, still rolling across I-80, and reports that The NetBeans Mobile is half way across the U.S. His latest report says he's "in Avoca, Iowa. Travelling is always an adventure, and this is no exception." 

In Java Today, Eduardo Pelegri-Llopart has announced the first version of a GlassFish User FAQ as part of the GlassFish Wiki. "Gail has started a GlassFish User FAQ and has posted a Contribution Process. Community members can contribute Qs and As. For example, Andreas contributed How to Configure Log4J and Ryan wrote about Running GF behind Apache. Read Gail's message for more details. It would be great to see many more entries answered by the time we get GFv2 FCS (next week, we hope). We will adjust the process as it goes; for example, we may want to add comments to validate the answers."

The Robotics Community's Etching Project takes an image and turns it into a vector list for an outline drawing. It was originally used to drive the ABB robot demo at JavaOne 2007. The IRB 340 robot used for the etching demo is the fastest in its class with 10G acceleration and 150 pick cycles per minute.

The JCP Program Office recently sent out an e-mail reminding JCP members to ensure their contact information is correct, as the 2007 JCP EC Elections get underway soon. All JCP program member primary contacts will be sent their voting PIN for the first phase of the Elections in early October. Voting for ratified seats will be held from October 2-15, followed by nominations for elected seats from October 16-26, and voting for those seats held October 30 - November 12.

In today's Forums, jay_levitt digs into rendering glitches and wonders if he's seeing Java2D/Swing problems w/small, bold fonts? "I've been using Eclipse for years on Windows XP SP2, no problems, but I wanted to try out NetBeans, which uses Swing instead of SWT. Oof! All the small (18pt and below) bold fonts looked chunky, blocky, almost like dot-matrix pseudo-bold. [...] It seems like Swing is not properly applying/emulating native font smoothing to bold fonts, while AWT is. And that this has been the case at least as far back as 1.5. And not fixed in 6. I find that hard to believe, so I must be doing something wrong. Please, God, let me be doing something wrong, because I wanna use a Swing app and not have my eyes hurt."

mdebac is trying to understand the implications of end-to-end wsit. "I have a doubt on how to achive en-to-end security use case with wsit. As I understood this is the major advantage over SSL, which is point-to-point security. Let's have some examle: we have app A which is connect to app B, and B is connect to C. So lets say that B is intermidiate app. We want that A call service at C, but that must go through B, where B can decript only one part of message, change it, and sign this part plus some second part of message. B in this couldnt see some part of message which are aimed to be only for A to decript and read. So A will succesfully validate message if he sees that expecialy some part are sign by B and the rest sign by C. Is this what we mean by end-to-end security? So should we declare more than one public keys at A (for B and C) for operation?"

Finally, brent_allsop apparently wants to run a background ME process on the phone, as explained in Re: Custom App for T-Mobile Wing? "The question I have now is, I'm trying to develop a background process that will always run on my wing, that will check a web site status every 5 minutes or so. The current MIDlet I've developed works great until you try to switch out of java and go back to normal phone mode. All the java MIDlet stuff suspends and doesn't run till you reactivate it. hope I can find a way to get a java MIDlet to run in the background!? Maybe I can somehow escape the MIDlet environment and run raw java? Any other possibilities?"

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Event handling getting out of hand?
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