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Client's transaction aborted

I've met the above error message using a Wicket 1.2 / EJB3 intranet application under Glassfish v2 . Here is the more particular head of the stack trace: javax.ejb.TransactionRolledbackLocalException: Client's transaction aborted at com.sun.ejb.containers.BaseContainer.useClientTx(BaseContainer.java:3394) at com.sun.ejb.containers.BaseContainer.preInvokeTx(BaseContainer.java:3274) at com.sun.ejb.containers.BaseContainer.preInvoke(BaseContainer.java:1244) at com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:195) at com.sun.ejb.containers.EJBLocalObjectInvocationHandlerDelegate.invoke(EJBLocalObjectInvocationHandlerDelegate.java:127) This exception raised on the integration server sometimes, randomly, for simple page fetch operations. After pressing reload on the browser, the operation was usually successful. I couldn't reproduce the failure on the local machine where I regularly restart the app server and

Eclipse DemoCamp Budapest

This year I also couldn't get to any of the heavy European Java conferences, so I stayed at visiting some tiny local events intown. For example last week I attended on the Eclipse DemoCamp Budapest which was organized by the right engaging b2i local team at a pleasant (but not too silent) downtown pub. Around 20 participant were present and there were two presentations, or rather demos planned. When people entered they were asked if they had some interesting subject to speak about, so the whole thing had an unconference style. FOT Testing Services guys actually had a notebook with a copy of their recent project so they took the opportunity to introduce it to the public. First demo was about making a generic data model with EMF (Eclipse Modeling Framework) plugin and creating a model editor with Eclipse GMF (Graphical Modeling Framework) which is given by GEF (Graphical Editing Framework). The example model was a basic CD database. With suitable experiences, it takes about 10-2

Cloud Computing

Is it the ultimate innovation or is it the next buzzword managers and sales staff members must record into their notebooks? After reading some material it doesn't mean more for me than a clustered client-server architecture where processing capacity and memory can be hired and clients are generally web browsers or other applications. It's not a big novelty form the developers' point of view so first of all we got a new phrase for the hot water. Don't mix it with 'grid computing' where real math computations are running on a statically or dynamically built distributed network (SETI@home for an example) and clients are active participants of the process. Instead of this, with cloud computing, you connect to the service and use it. So I don't get again where is the magic. (Maybe the magic is in the ability of obtaining a large amount of personal data and money from the users.) I can imagine an architecture which discovers (sourceforge does this) or even deplo

Setting up EJB3 default interceptor

It wasn't easy to find out how to configure a default interceptor in EJB3 environment. It's okay to make this snippet into the ejb-jar.xml: <assembly-descriptor> <interceptor-binding> <ejb-name>*</ejb-name> <interceptor-class>pkg.IC</interceptor-class> </interceptor-binding> </assembly-descriptor> Maybe everybody forget to mention maybe it's a Glassfish V2 trick that I get this error message during deployment: Interceptor binding contains an interceptor class name = pkg.IC that is not defined as an interceptor ...unless I register the interceptor class itself too with this: <interceptors> <interceptor> <interceptor-class>pkg.IC</interceptor-class> <around-invoke> <method-name>call</method-name> </around-invoke> </interceptor> </interceptors> <interceptors> and <as

Survey

Some months ago I read an article which said programmers usually do their hobby projects much better than their working projects. There are several reasons like time-pressure, predefined set of useless tools and pointless procedures, rubber specifications etc. I've made a little survey about that. Do you feel sometimes it would be better to be a shepherd somewhere on a sympathetic highland in, say, Scotland and to forget all office crap? Or do you arrive at yor workplace every morning that you know you will change the world a little, of course in the right direction? The survey is here at the right. Thank you for giving an answer if you did. It would be nice to know the distribution of the answers by several categories like programming languages, destination environments, open source and commercial projects, speciality of the projects (banking, science, administration, telecommunications, entertainment, web/publishing), however, this simple survey is not capable for that. But I hav

AppServer Shootout

Recently we organized an AppServer shootout (we call it deatmatch) on our local Java User Meeting. The three contestants would have been Sun's Glassfish v2, Redhat's JBoss and IBM's Geronimo. Unfortunately IBM guy couldn't attend on this event because of other business and JBoss presentation had technical difficulties so we had to do with Glassfish demo. Let's see the 8 tasks: 1. Deploying simple EJB3/JPA webapplication with pre-initialized DB. Checking WSDL as a bonus. It was easy and elegant. We checked WSDL which was an ugly and large XML but it's been generated automatically. We did a test request by using the Glassfish's admin console. That means we filled an HTML form containing one of the webservice's method's parameters and submitted it. 2. Remote deploy from build script. (Usual development task.) We did it from Netbeans using Ant and a special Glassfish deploy task. AFAIK hot deploy is also supported by Glassfish when appserver scans a pre-

Challenge24 EC

Challenge24 had been started as an internal competition at the local techincal university of Budapest. For now it became an international programming contest which is being organized 8th time this year. The contest itself usually happens in May when teams must be present personally but it's preceeded by a qualifying session (a.k.a Electronic Contest ) which has been arranged on the last weekend of February and teams didn't have to be present personally, just to be online. At Electronic Contest there are up to 8 combinatorical, geometrical, game theorical problems which have to be solved by sending the result files to the central server. Teams are free to choose platform and programming language. More information including rules, list of teams and their scores, assignment of the Electronic Contest can be found on the homepage . The name is Challenge24, because the main contest in May lasts for 24 hours. I didn't take part nor this year nor earlier but I usually download and

JavaPosse Episode 157

Why do I post these? I've been regularly listening these podcasts and sometimes I flag more interesting subjects in order to be able to re-listen them. It's just one step forward to flag *all* main subjects and make it public whether it's useful for others. This one was the latest Episode in 2007 or the first in 2008 depending on the point of view. With this, all tracklists of 2008-episodes are present up to now. Further ones are posted to the JavaPosse Google Group. Henceforward, I plan to write real posts here. :) Original shownotes and the audible mp3 of the podcast can be found here . More tracklists can be found here . 00:10 Metal theme, intro 03:40 Announcing JavaPosse Roundup 09:35 'Smart Drink Coasters - Digital Pub' / Is java slow? 14:00 Is java loosing place? Reflecting for weird articles. 21:55 What did you give for Christmas? 31:55 Favourite aspect or moments of the year 33:10 JavaPosse Google Group 41:40 Last year predictions 45:50 Predictions for next

JavaPosse Episode 158

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found here . More tracklists can be found here . Newcast for January 9th 2008 00:25 Intro (T-shirt is available) 01:44 Roundup - only days left for the early bird price 02:35 Bruce Eckel: should we simply stop adding new features to Java? 17:40 Apple has released an updated developer preview version of Java 6 22:50 Two Professors from NYU have slammed Java as a teaching language 33:20 Scala Roundup 38:00 Library of the week - PDF Renderer 40:30 Up and coming Project of the Week - Mighty Box Quick News Items 44:00 JSR 271 - The Mobile Information Device Profile 3 (better known as MIDP 3) 44:23 Chris Adamson has issued a call for comments on how java.net might be improved in 2008 44:48 Is Rails a Ghetto? 45:51 Apache Wicket 1.3 has been released 46:09 Motorola has released a new version of the ROKR music playing phone 46:15 JSR 286 - the Java Portlet Specification 2.0 46:33 JSR 255 - JMX (the Java M

JavaPosse Episode 163

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found Shownotes . More tracklists can be found More Tracklists . 00:30 Intro -couple of guests in studio, club feeling, somebody is speaking from the cupboard. Roundup, Sun / MySQL, etc. 17:28 Grails 1.0 released 21:10 Registration for JavaOne is now open 30:25 Closures 38:50 JSF has passed Swing as the number one GUI component model for job demand 42:20 JavaFX update N, reinventing client Java 49:40 Nymbus Look and Feel 52:10 Font rendering Quick News 64:00 A NetBeans Innovators Grants program has been introduced by Sun 64:50 How to write a full application that uses JSF, Seam 2.0 and JPA together, Carol McDonald's blog 65:26 Duke's Choice Award (deadline is 14th March) 65:40 Opera Mobile 69:37 TheServerSide.com has an introduction to using MapReduce in Java applications 69:58 Sun has released a new version of their Solaris Express Developer Edition 70:57 Sun has also posted a pro

JavaPosse Episode 162

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found here . More tracklists can be found here . Interview with Dalibor Topic about Open JDK, the JCP, Kaffe, Iced Tea and more 00:40 Intro 01:44 About Kaffe project 05:28 What's the current state of Kaffe now? 07:35 Are annotations and generics supported by Kaffe now? 09:15 What were the trade-offs between those two licenses and why did you end up picking the GPL side of the two? 10:45 How difficult is it to hit a moving target like the Java Language Specification in a project like Kaffe? 12:26 What do you think is the future for Kaffe? 14:25 ... Are you seeing now that OpenJDK is open sourced or at least mostly open sourced that it's definitely being picked up from those kind of distributions? (Java in Linux) 16:25 Any other project you are involved? (GNU classpath) 17:20 Dalibor's relationship with OpenJDK. 20:33 The OpenJDK was released under the GPLv2 with the classpath exception.

JavaPosse Episode 161

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found here . More tracklists can be found here . Open JavaME and JavaSE interviews 00:30 Intro : About roundup signups, skiing, next episode (will be a listener feedback session), etc 05:00 About interview at Sun Java Mobile and Embedded Developer Days 06:10 Sun aquiring MySQL 12:52 Oracle acquiring BEA 17:25 Is the Geronimo in trouble? 20:00 Applet of the Week: Sea Level applets 21:05 Project of the week - LoboBrowser Quick News 23:43 JDK6u4 24:00 CommunityOne 2008 call for participation 24:38 JavaZone 2008 call for presentations 25:17 Jazoon 08 25:50 EclipseCon 26:21 Artifactory, Maven 26:34 Chris Richardson's blog entry 27:04 JSR 323 - Strong Mobility for Java 27:41 Bill Venners has released a new testing tool - ScalaTest ('JUnit for Scala') 28:06 The Developer.com product awards for 2008 have been announced 28:32 JackRabbit 1.4 28:49 Apache Jakarta Commons Pool 1.4 29:10 Neal Gafte

JavaPosse Episode 159

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found here . More tracklists can be found here . Open source ME and SE interviews 00:30 Intro, background 01:16 Interview with Terence Barr, introduction 02:11 What happened since the announcement of open sourcing JavaME? 03:21 What were the reasons for applying GPLv2 without the classpath exception? Has it turned out to be a good choice in retrospect? 05:53 Had commercial licensees react to the open sourcing of JavaME? 07:42 What the deal is with JavaME CLDC and JavaME CDC? It was reported earlier that CLDC was being killed. What's going on here? 10:02 Have you seen any unusual or unexpected port JavaME since it was open sourced? 12:52 Do you think JavaME development has accelerated as a result of its open sourcing? 14:06 How will the JavaFX script work in JavaME? When will we see FX script running on mobile devices any time soon? 15:45 What's the story with device availability? Are there

JavaPosse Episode 155

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found here . More tracklists can be found here . 00:25 Prologue 00:50 Introducing Martin Odersky 05:14 How long have you been working on Scala? 06:35 Do you think Scala can be a general purpose language? 08:58 Why Scala is a much more practical approach to functional programming than something like Miranda is? 11:37 What are monets? (?) 13:42 What do you suggest for Java programmers to get started in Scala? (First steps to Scala) 17:16 Earliest real world examples of Scala usage 20:00 What other applications do you see as perfect fits for Scala? 22:00 Why immutability is kind of that important in functional languages or Scala? 24:10 About XML 'efficiency' in Java 26:00 What do you think about closures in Java? 28:28 Embedding XML in Scala 30:52 What's your strategy about (backward) compatibility? 34:00 ending

JavaPosse Episode 153

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found here . More tracklists can be found here . Newscast for Dec 6th 2007 02:55 NetBeans 6.0 GWT plugin, Scala plugin(s) 09:05 Spring 2.5 has been released 11:25 Applets of the Week: Maths, Physics and Engineering applets 14:30 Android news: Robert Cooper's article 15:20 Carlos Bazarella from Polipus, ME4Android 15:40 OHA member Ascender announced 'Droid Fonts' 16:52 Starting with android. Article from John Lombardo 17:12 AndroidPort - new Google Group 17:22 Karl Pauls of Luminis has managed, to get Apache Felix to work on Android Quick New Items 17:44 TheServerSide article about RestFaces 18:45 Mark Reinhold, Governance Board 20:00 Think Record Storage 20:30 Atlassian Software has released version 1.2 of Crowd 20:50 The Apache project has released version 1.1 Final of Continuum 21:00 JBoss has released a JSF unit testing tool: JSFUnit 21:46 Project Mojarra 23:46 JSR321 - Trusted Comp

JavaPosse Episode 160

This is a tracklist of a JavaPosse Episode. Original shownotes and the audible mp3 can be found here . More tracklists can be found here . Interview with Bob Lee about Guice (Guice is an IoC framework.) 00:30 Intro 00:47 What is Guice? 03:56 What was the reason to start a new framework? 10:23 Have you seen people use it for really small things? 12:51 What's coming up? 22:50 Some things about Google Collections API 23:55 Differences between weak and soft references 26:15 Interesting combinations of strong and weak references in practice 28:18 What are the other things that you think are coming in the future for Google Collections? 30:30 Anything else, goodbye, outro...

Nav N Go @ CES Las Vegas

It always inflates me with pride when I see a Hungarian company at a famouns international exhibition . Many tiny software companies in Hungary are usually forming for optimizing income and for supplying ordinary software demands of other tiny companies which have not too much aim beside optimizing income and supplying some ordinary human demands. No creative ideas, just for hunting contracts and tenders on more or less fair ways. After reading their story I guess Nav N Go absolutely doesn't belong to this gang. They deal with car navigation systems and as I far I know they are market leader in the European region.