Tips: How to configure a Cluster of JMS Messaging on Jboss 5.1.0
Last week I lost a lot of time to obtain a perfect Jboss AS Cluster with JMS Messaging, now I am writing here some tips in order to avoid other wast time in the future 
To configure a cluster of Jboss it’s very easy, but for having a right JMS Messaging configuration could be too difficult.
For example, in my case I configured a jboss cluster, with two node (A & B) but just one node at time read the messages from the queue. It was an active-passive cluster. I would a real active-active cluster with load balacing policy.
First of all you need to configure at least 2 nodes starting from “all” configuration (e.g. nodeA & nodeB).
In this example I am going to explain how to configure the JMS messaging with a Oracle persistence.
Tips: How to configure Multiple domains on Apache Web Server and Tomcat
Last week I bought a new very nice and cheap VPS hosting (wooservers.com), I chosen Linux Debian 6 as operating system, and immediately after I moved on it some web-site/application hosted in different placed.
To do it I configured an Apache Web server for managing HTML and PHP sites (domain1.com / domain2.com) and a Tomcat Server for hosting Java application (domain3.com / domain4.com).
Every website has a really domain associated. Hereafter I collected all steps followed in order to configure several virtual-hosts on Apache Webserver for all domains, and a sub-set of them virtual-hosts on Tomcat for Java application.
Tips: Joomla MySQL jos_session is marked as crashed and should be repaired
“Hello”
“Hi Davide… our company website seems down since yesterday afternoon. Could you check? Yesterday there was a power problem in our datacenter”.
The error reported it was:
DB function failed with error number 145 'TABLE\ jos_session' is marked as crashed and should be repaired SQL=SELECT session_id FROM jos_session WHERE session_id ....
Woow, It’s very simple to solve the problem.
Go into your Mysql administrator website (via phpmyadmin, sqlyoog or others similar tools) for executing the following commands:
REPAIR TABLE jos_session
DELETE FROM jos_session
A possible Concurrency Producer and Consumer pattern
Often I discuss about concurrency problems and how to design applications that involved Producer and Consumer actors.
Thanks to my RSS feed I found an interesting article to discuss three different approach to read – process- update massive data.
The problem is:
- Load data based on Database based on groups
- Process the data
- Update the records loaded in step 1 with modifications
OCAJP & OCPJP – Oracle Java 7 Certification
Oracle released a new certification exame for Java 7.
At the moment there are just 2 certification:
- Oracle Certified Associate, JAVA SE 7 Programmer
- Oracle Certified Professional, JAVA SE 7 Programmer
As usual, Associate certification is a pre-requisit of Professional certification.
Job Trends for programming languages
I am always very interesting to new programming languages and how I have to improve my skills to be up to date with market requires and to address customers needs.
I found two interesting posts on regulargeek.com with programming languages trends:
- Tradional Programming languanges trends.
- “New” programming languanges trends.. or better to say unusual languages for enterprise sectors.
What Do’s and Don’ts during a conference call
Conference call is a fast method, and “cheaper”, to have a quickly meeting among people not near to their… but sometimes to do a call conference, and to understand all words, it’s very complex.
Here, some very easy tips:
TO DO
- Use mute “function” on your phone where you are not speaking.
- Stay away from other people / colleagues.
- Don’t speak too close to your microphone.
- Don’t use “hold” function on your phone… so don’t answer to another call that you can receive in the meantime.
Oracle Virtual Machine pre-built with Database, Weblogic and developers tools
Woow.. last week I discovered a useful link posted by oracle.com to obtain pre-built virtual machine, based on VirtualBox, for developing purpose.
Here you find a little description and the link to download it.
Oracle Database development virtual machine [Download]
- Oracle Linux 5
- Oracle Database 11g Release 2
- Oracle XML DB
- Oracle SQL Developer
- Oracle JDeveloper
Job Interview, Questions to hire a Java and J2EE Developers
As first post on this blog I chosen a not very “geek” article.
Often I am finding and thinking some questions to find smart Java and J2EE developers.
Thanks to Internet (specially Java code geeks) and to my colleagues (Lorenzo & Daniele) I decided to collect here a set of good questions.
Very good thing if you want add others questions or doubts as comments… thanks!
First of all I think it’s better to ask a self-evaluation about skills / main frameworks then with some quickly questions you can confirm it.
