Hibernate's implementation of JPA has some quirks, such as not being able to handle the eager fetching of two @OneToMany relationships in a single entity without the use of some work-arounds. Although this article is not about these work-arounds I will give a quick overview of the problem and solution to that problem first, before looking at the specifics of the case where I got the error on a entity with two @ManyToOne.

Saturday, was the 1 st September,the first official day of spring. Besides being a Saturday for a change the day was gloriously warm and sunny. Everything that spring day should be. I spent most of the morning outdoors, walking the dogs, enjoying the warmth and planning my first screencast.

The other day I suddenly started getting this error when running maven 2 on my gentoo box.

Exception in thread "main" java.lang.NoClassDefFoundError: org/codehaus/classworlds/Launcher

Struts Validations Framework How to

The struts validation framework is quiet straight forward to use but there are lots of little gotchas that slow down the learning process. It should take one no more than two hours to understand and use the validation framework. Here are some of pointers that help new users of the framework.

A while ago I was researching open source business intelligence applications and came across some real gems that I thought I should share with others. The two big projects I found are Openi and Pentaho. Pentaho is an Eclipse based product and gives developers a complete platform for BI application development based on open source and Java.