« Archives in February, 2010

*nix commands I can’t do without

February 13, 2010 / posted in Fedora / 10 Comments

Unix/Linux/*nix survival 101

Let me start with the obvious: I’m definitely not a unix guru by any means. I do however use it on a daily basis for basic build/development oriented tasks, so I know enough to get by. Since my friend just installed his first ever linux distribution (CentOS, Huzzah!), I thought I’d write something up on some common unix commands that help me get through the day.

grep [command flags] [search text] [filename]

grep (global | regular expression | print) is the file text search command. Give it a regular expression and it will print out…

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Transforming XML into MS Excel XML

February 9, 2010 / posted in xml / No Comments

MS Excel understands XML?

If you need to export xml to a Microsoft Excel friendly format, you could stress over the HSSF (Horrible Spread Sheet Format, for the uninitiated) format with apache’s POI framework or you could transform your xml into an format Excel understands. This approach will allow you to decorate your cells with stylized fonts and borders; what it will not allow you to do is create or add complex objects like charts, graphs or pictures. This xml format is a watered down version of excel. If you require the ability to embed images, graphs…

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Integrating Spring MVC 3.0 with JSR 303 (aka javax.validation.*)

February 8, 2010 / posted in Java / 39 Comments

Annotated POJO validation comes to a JDK near you!

The new annotated validation spec (jsr 303) is pretty slick, especially when used along side Spring MVC 3.0, and when backed by ejb3 entities. I’m pretty impressed with how easily it integrates with Spring MVC’s framework, and with how seamlessly error messages are passed to the form taglibs so they show up in your web forms.

I know some of you might argue that the current validation framework might not address complex validations, but after giving Hibernate’s reference implementation documentation a look, it seems interdependent validations are at least…

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Quartz Scheduled Jobs – v1.5.2

February 5, 2010 / posted in Java / 7 Comments

Java, XML, and cron driven scheduling made easy.

Projects here and there often need some kind of mechanism to schedule jobs at odd hours, or intervals. Quartz is a robust, flexible tool you can use to accomplish simple to complex job scheduling. There are a number of ways to use/configure quartz, but I’ve grown accustomed to using it with an xml based configuration. There are a few things we need to set up unfortunately, so there is a certain amount of plumbing we need to work out, but once that infrastructure is set up, its much less work…

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Ejb3 Basics: Deploying Message Driven Beans

February 2, 2010 / posted in Java, Jboss / 2 Comments

Farewell to lazy auto queue generation in JBoss 5

MDB’s were never so easy to deploy and manage when ejb3 first came out. In Jboss 4, all you have to do was annotate a class with @MessageDriven, sprinkle some meta data here and there, stick it in the oven and wham! Instant “I cant believe I made an MDB!?!” In Jboss AS 5 however, MDB queues are no longer automatically created for your application anymore on boot. An inspection of the MDB llifecycle illustrates why:

  1. MDB deploys
  2. No existing Topic/Queue
  3. Topic/Queue is automatically created
  4. MDB is

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